Spring Shackles
------------------------------
Date: Sun, 9 Mar 1997 00:46:35 -800
From: "Ken Emanuel"
Subject: Spring Shackles
To: Toy4X4@tlca.org
>I haven't heard of one (1/2" lift block) but they might be available.
>Seems like you could make one very easy with a chunk of 1/2" aluminum or
>steel. I bet the shop would cut it out for very little money, and all you
>would need to do would be to drill the hole, replace the bolt running
>through the springs, and replace the u-bolts.
>...An easier way would just to get a set of 1" or so longer rear shackles.
>I seriously doubt that these would effect ride, handling, spring
>longetivity or anything else--plus they'd be easier to put on than
>blocks.
>I really don't see how longer shackles could 'put bends in the springs.'
>Have you seen this before? Just curious...
Anyone can correct me if I am wrong, but adding shackles to the
rear of the springs (since we are talking about the rear of the
truck) has the effect of putting more pressure on the
rear of the spring. If you look at the springs, you
will notice that the other leaves are closer to the front of the
spring that the rear, so not only are you adding pressure on the rear
of the spring, but the other springs aren't operating as they are
supposed to because spring pressure has been moved rearward. Once
you have added extended shackles, you will find that when you remove
them, your truck will sag worse than ever because you have put more
stress on the springs. Also, lengthened shackles will (and do)
increase axle wrap. Since more pressure is on the rear of the
spring, and the other two springs are helping less, the spring moves
easier, making axle wrap a lot more noticeable.
Thanks for the information, I am going to go with the 1/2" lift
block, even if I have to fabricate it.
Ken Emanuel
1987 Toyota Xtra Cab SR5
------------------------------
Date: Thu, 13 Mar 1997 21:39:55 -0800 (PST)
From: Jonathan Albrecht
Subject: Spring Shackles
To: Toy4x4@tlca.org
On Sun, 9 Mar 1997, Ken Emanuel wrote:
> >I really don't see how longer shackles could 'put bends in the springs.'
> >Have you seen this before? Just curious...
> easier, making axle wrap a lot more noticeable.
> Thanks for the information, I am going to go with the 1/2" lift
> block, even if I have to fabricate it.
hmm, that's interesting. I guess you could be right (about the longer
shackle being harder on the spring)... One of my friends is running
downey's longest shackles, Rancho's short add-a-leaf, and a 4" block. So
far, no problems (knock on wood)...
YMMV
Jonathan Albrecht
albr9619@uidaho.edu
http://www.uidaho.edu/~albr9619/
------------------------------
------------------------------
Date: Fri, 14 Mar 1997 08:00:35 -0800
From: Eric Johnson
Subject: Spring Shackles
To: "'Toy4x4@tlca.org'"
On Saturday, March 08, 1997 4:46 PM, Ken=20
[snip]
> Anyone can correct me if I am wrong, but adding shackles to the=20
> rear of the springs (since we are talking about the rear of the=20
> truck) has the effect of putting more pressure on the=20
> rear of the spring. If you look at the springs, you=20
> will notice that the other leaves are closer to the front of the=20
> spring that the rear, so not only are you adding pressure on the rear=20
> of the spring, but the other springs aren't operating as they are=20
> supposed to because spring pressure has been moved rearward. =20
Here we go again... :) Granted, the geometry is a little different (but =
we;re only talking about an inch or so right?) Seems to me the geometry =
would suggest more pressure on the front, but just like the torsion bar =
debate, you can't add more force to the spring unless you make it hold =
more weight. You CAN effect whether the relative weight being borne by =
the front or the rear of the spring, but only to the extent that the =
axle moves forward or backward relative to its original position, which =
in this case is nil... Shackles DO increase the compression travel of =
the rear springs, which may be bad for the springs if they compress =
beyond what they are capable of doing. I've been extremely happy with my =
shackles, the extra travel has helped out on a number of occasions.
> Once=20
> you have added extended shackles, you will find that when you remove=20
> them, your truck will sag worse than ever because you have put more=20
> stress on the springs.
Has anyone experienced this?
> Also, lengthened shackles will (and do)
> increase axle wrap. Since more pressure is on the rear of the
> spring, and the other two springs are helping less, the spring moves
> easier, making axle wrap a lot more noticeable.
I get 50% more axle wrap. 1.50 x 0 =3D 0 :) I've never noticed axle wrap
with or without shackles on my rig. Of course, I'm running a 22RE with a
A340H, so I'm not exactly dumping tons of horsepower into it :)
Shackles definitely promote axle wrap LESS than an equivalent block...
but I don't want to get into the moment-arm thing again :)
We got a lot of voodoo physics around here...
- --
- - ej@blarg.net
------------------------------
Date: Fri, 14 Mar 1997 12:32:58 MST7MDT
From: "Alan Anderson"
Subject: spring shackles...
To: Toy4x4@tlca.org
Hello all,
I was wondering if there is anyone on the list from the So. Idaho
area? If so would you like to join an Off-Road club? We are trying to
get one started....
With all the talk about longer than stock spring shackles, I was
wondering if anyone has built any custom shackles themselves?
If so did you make a braced/unbraced type? I wanted to make a set
for my toy....I was thinking about an unbraced type to get more axle
articulation....If someone has done this, what did you make them out
of? Will mild steel work? I was thinking about 3/8in. plate or
strap...Ideas? I am lookin for about 1-1/2 to 2in. of lift...but
mainly more articulation.... Jack, Jay,?, give me a hand here....
Please send to my E-mail as well as the list
Thanx,
------------------------------
Date: Fri, 14 Mar 1997 14:45:25 -0600
From: Jack Alford
Subject: spring shackles...
To: toy4x4@tlca.org
Alan Anderson" wrote:
> With all the talk about longer than stock spring shackles, I was
>wondering if anyone has built any custom shackles themselves?
>If so did you make a braced/unbraced type? I wanted to make a set
>for my toy....I was thinking about an unbraced type to get more axle
>articulation....If someone has done this, what did you make them out
>of? Will mild steel work? I was thinking about 3/8in. plate or
>strap...Ideas? I am lookin for about 1-1/2 to 2in. of lift...but
>mainly more articulation.... Jack, Jay,?, give me a hand here....
I've made and modified a few pairs. If you're going to make a set of
unbraced ones then I'd use 3/8" x 2" plate. If you're going to
make them braced 1/4" x 2" would suffice depending upon how long
you're going to make them and whether or not you're going to put
them on the front or the rear. Just average mild steel will work fine,
I buy all my steel from the scrap yard ...
-----------------------------------------------------------------
Jack Alford Off-Road.com - The best dirt on the net!
jalford@off-road.com http://www.off-road.com/
Decatur, AL
'86 Xcab Toyota Pickup - 33x12.50 BFG MT
Solid Front Axle - Marlin Crawler - ARB's - 4.88's
SFWDA - TLCA #3415 - Rocket City Rock Crawlers
------------------------------
------------------------------
Date: 17 Mar 1997 15:00:04 U
From: "Jay Kopycinski"
Subject: spring shackles...
To: "Toyota 4x4 List"
Subject: Time: 1:16 PM
OFFICE MEMO spring shackles... Date: 3/17/97
Alan Anderson" wrote:
> With all the talk about longer than stock spring shackles, I was
>wondering if anyone has built any custom shackles themselves?
>If so did you make a braced/unbraced type? I wanted to make a set
>for my toy....I was thinking about an unbraced type to get more axle
>articulation....If someone has done this, what did you make them out
>of? Will mild steel work? I was thinking about 3/8in. plate or
>strap...Ideas? I am lookin for about 1-1/2 to 2in. of lift...but
>mainly more articulation.... Jack, Jay,?, give me a hand here....
I've made a few pair. I've made braced ones from 1.5" x 1/4"
flat bar with 2.5" x 1.5" box steel as a brace. My latest ones
are made from 2" x 3/8" flat bar without a brace.
I drilled a 1/2" hole in the middle of each of them in case I ever
want to add a brace. I'd use a 1/2" bolt, a nyloc nut, and a piece of
tube for a brace that could be easily removed.
_____________________________________________
Jay Kopycinski '85 Toylet (ROKTOY)
Gilbert, AZ
ryna10@email.sps.mot.com
http://www.netzone.com/~jayk
Arizona Lo-Rangers 4WD Club TLCA #3243
_____________________________________________
------------------------------
------------------------------
Date: 19 Mar 1997 10:24:28 U
From: "Jay Kopycinski"
Subject: spring shackles...
To: "Toyota 4x4 List"
Subject: Time: 8:49 AM
OFFICE MEMO spring shackles... Date: 3/19/97
matt877@juno.com (Matthew C Chapin) wrote:
Subject: spring shackles...
>Tell me what are the advantages/disadvantages to braceing a shackle? I
>have a pair on that are not braced they work fine but I am worried that
>they may not be as safe as I should be running. Should I brace them?
Braced shackles provide greater on-road stability, but may limit
suspension articulation. The longer the shackle is, the more you
may need to consider bracing them. Unbraced shackles should also
(IMHO) be made from thicker material. I prefer 1/4" steel for braced
and 3/8" steel for unbraced.
My current shackles are unbraced but I have drilled 1/2" holes in
them to install a brace later if needed. The bushing bolts currently
fit fairly close and I find no problems running them at high speed
on the highway. As they wear (and the bolt/hole mating gets sloppier),
I may add a brace when running on the highway.
_____________________________________________
Jay Kopycinski '85 Toylet (ROKTOY)
Gilbert, AZ
ryna10@email.sps.mot.com
http://www.netzone.com/~jayk
Arizona Lo-Rangers 4WD Club TLCA #3243
_____________________________________________
------------------------------
------------------------------
Date: Fri, 25 Apr 1997 09:21:04 -0400
From: Ed.Wong@astramerck.com
Subject: The shackle and and spring rate stuff..
To: " - (052)Toy4x4 (a) tlca.org"
I've been reading this thread with some mild amusement over the last week or
so...
The angles can be calculated, graphed and even "optimized" (potentially,
I haven't done the math yet).
Umm - try 3 semesters of calculus and both statics and dynamics - this is
usually complete by the end of sophmore year in engineering school.
Actually this thread reminds me of that "offset piston wrist pin" thing going
on in the circle track world.
Anway - to start - map out the two fixed points ( the frame eye for the
spring and the frame eye for the shackle)
to make it REALLY easy - assume a solid (infinitely stiff) spring
draw it out as a triangle. pick a fixed height (it doesnt matter - you're
calculating deltas not absolutes) for the frame mounting points.
express shackle position (spring eye height) as a equation of the pin
location (i.e the axle position)
Look at the delta height of the spring eye over the delta height of the axle
either plug and play for the spring length and shackle length or start doing
more calculus (max and min the equations)
Math CAD programs help here - they can graph the equations and you can look
for "weird" spots on the curve - local min and such.
If yer Richard Feynmann - you've already done this and devised a
sliding shackle arrangement or something goofy (eccentric spring piviot
bolts?)
Yes - if you get complicated, you can enter the spring rates into the
equation as a function of spring deflection at a certian heignt (simple way)
or as a full calculation of the expected deflection at a certian position
(more complicated - possibly more accurate but probably NOT)
Race car teams are starting to get into this stuff - but have found that
optimizing all this sometimes has more to do with intuition rather than raw
numbers.
EWong
------------------------------
Date: 14 Apr 1997 09:05:33 U
From: "Jay Kopycinski"
Subject: Shackles
To: "Toyota 4x4 List"
Subject: Time: 8:35 AM
OFFICE MEMO Shackles Date: 4/14/97
rob and karen boyle wrote:
snip
>#2 I'm gonna make my own shackles to raise the rear to the procomp lift
>hight there are black diamond add a leafs back their allready (2'' mabye)
>and I think I can shackle lift the other two inches. I have a metal fab shop
>at my disposal. any guess what hole spacing and the preferred thickness of
>flat stock to use?
I've found 3/8" x 2" flat stock works great for unbraced shackles. I think
you will need a hole spacing of about 7.5" (stock 3.5" + 4") for your two
inch lift.
_____________________________________________
Jay Kopycinski '85 Toylet (ROKTOY)
Gilbert, AZ
ryna10@email.sps.mot.com
http://www.netzone.com/~jayk
Arizona Lo-Rangers 4WD Club TLCA #3243
_____________________________________________
------------------------------
------------------------------
Date: Thu, 17 Apr 1997 09:46:50 -0400 (EDT)
From: DRM033@aol.com
Subject: shackle length v. lift heigth
To: Toy4x4@tlca.org
In a message dated 97-04-17 09:21:47 EDT, you write:
> I still feel that if you lift a truck with a 2" longer shackle, the truck
> isn't lifted a full two inches. It may not be exactly 1/2 that, but it
> will only be about 1-1.3" higher. If the shackle is at roughly the same
> position (nearly perpendicular to the ground), and is 2" longer than
> stock, but the truck only sits 1-1.3" higher...the bottom end of the
> shackle has GOTTA be lower.
>
> I'm pretty sure of myself on this one, but I could be wrong. I'm
> open to comments.
> __
> Jonathan Albrecht
> albr9619@uidaho.edu
> http://www.uidaho.edu/~albr9619/
>
I will admit, my "shackle angle" theory is faulty.
Try this one
OK, here is a test you can do. Take a pencil. This is your "spring". Put
one end on the table, elevate the other end 2" in the air. Now, take your
measurement from the center of the pencil. Should be 1". The center is
where the axle would be located. The end on the table is the spring's fixed
point. The end in the air is the shackle. That explains the reason the lift
is not = to shackle length.
S for the spring eye being lower, I will have to say I was wrong. As to it
changing departure angle, 1" should not be a factor, considering that the
shackle is usually coupled with larger tires.
What I meant by optical illusion, it what just because the shackle is longer,
is *should not* come between the line from the tire to the rear lowest point.
Also , you have in essence lowered the tire, changing the departure angle.
the 1" inch lift change and the 1" (splitting the 2") lower spring eye shoud
kinda cancel each other. If this is way off, I would like to know.
David
DRM033@aol.com
------------------------------
Date: Thu, 17 Apr 1997 07:58:00 -0700
From: Scott Wilson
Subject: shackle length v. lift heigth
To: Toy4x4@tlca.org
Jonathan Albrecht wrote:
> I still feel that if you lift a truck with a 2" longer shackle, the truck
> isn't lifted a full two inches. It may not be exactly 1/2 that, but it
> will only be about 1-1.3" higher. If the shackle is at roughly the same
> position (nearly perpendicular to the ground), and is 2" longer than
> stock, but the truck only sits 1-1.3" higher...the bottom end of the
> shackle has GOTTA be lower.
FWIW, I used a 3"(longer than stock) shackle on my 88 4Runner and my
lift was exactly 2".
Scott
- --
Scott A. Wilson __o __o __o __o
Santa Clara, CA _'\<,_ _'\<,_ _'\<,_ _'\<,_
swilson@pacbell.net (_)' (_) (_)' (_) (_)' (_) (_)' (_)
http://users.uniserve.com/~rcomber/scottw/scottw.htm
------------------------------
Date: Thu, 17 Apr 1997 11:59:58 -0500
From: Jack Alford
Subject: shackle length v. lift heigth
To: toy4x4@tlca.org
Man, you guys have beat this 'shackle length' horse to death ...
>FWIW, I used a 3"(longer than stock) shackle on my 88 4Runner and my
>lift was exactly 2".
The others argument of shackle length = 1/2 lift height gained does not
truly equate on Toyota springs because the axle is not in the middle of
springs but the length=1/2 lift gained is a good rule of thumb in most
cases.
-----------------------------------------------------------------
Jack Alford Off-Road.com - The best dirt on the net!
jalford@off-road.com http://www.off-road.com/
Decatur, AL
'86 Xcab Toyota Pickup - 33x12.50 BFG MT
Solid Front Axle - Marlin Crawler - ARB's - 4.88's
SFWDA - TLCA #3415 - Rocket City Rock Crawlers
------------------------------
Date: Thu, 17 Apr 1997 15:10:01 -0700 (PDT)
From: Jonathan Albrecht
Subject: shackle length v. lift heigth
To: Toy4x4@tlca.org
sorry about reposting most of this measage..
I said:
> > I still feel that if you lift a truck with a 2" longer shackle, the truck
> > isn't lifted a full two inches. It may not be exactly 1/2 that, but it
> > will only be about 1-1.3" higher. If the shackle is at roughly the same
> > position (nearly perpendicular to the ground), and is 2" longer than
> > stock, but the truck only sits 1-1.3" higher...the bottom end of the
> > shackle has GOTTA be lower.
david said:
> I will admit, my "shackle angle" theory is faulty.
> Try this one
> OK, here is a test you can do. Take a pencil. This is your "spring". Put
> one end on the table, elevate the other end 2" in the air. Now, take your
> measurement from the center of the pencil. Should be 1". The center is
> where the axle would be located. The end on the table is the spring's fixed
> point. The end in the air is the shackle. That explains the reason the lift
> is not = to shackle length.
agreed
> So for the spring eye being lower, I will have to say I was wrong. As
> to it changing departure angle, 1" should not be a factor, considering
> that the shackle is usually coupled with larger tires. What I meant by
> optical illusion, it what just because the shackle is longer, is *should
> not* come between the line from the tire to the rear lowest point.
I think this kinda depends upon a lot of things. Usually my reciever
hitch would hit before my 2.5" longer shackles would. If I drove off a
ledge though, the shackle would hit (and drag) and then the reciever would
hit (and drag). I guess the lower shackles never really caused any
problems even when they did drag...though it could if you tried to back up
on a steep ledge (where the ledge was below the bumper, but above the
shackle).
> Also , you have in essence lowered the tire, changing the departure angle.
> the 1" inch lift change and the 1" (splitting the 2") lower spring eye shoud
> kinda cancel each other. If this is way off, I would like to know.
I think we both agree on everything 'cept for this last comment. I still
feel that if the truck is 1" higher, and the shackle is 2" longer, then
the bottom of it will be 1" lower than before.
I wouldn't say that the 1" lift would cancel the 1" lower shackle but
rather because of the 1" lift, the bottom of the 2" longer shackle is
only 1" lower.
Here's a better solution--could someone with extended shackles measure the
distance from the bottom of your shackle to the ground, and then measure
the distance from the bottom of the shackle on a similar year, similarly
set up truck (with stock shackles)?
__
Jonathan Albrecht
albr9619@uidaho.edu
http://www.uidaho.edu/~albr9619/
------------------------------
Date: Thu, 17 Apr 1997 15:24:20 -0800
From: Scott Wilson
Subject: shackle length v. lift heigth
To: Toy4x4@tlca.org
Jonathan Albrecht wrote:
> I think we both agree on everything 'cept for this last comment. I still
> feel that if the truck is 1" higher, and the shackle is 2" longer, then
> the bottom of it will be 1" lower than before.
>
I haven't really been following this thread, but...simple geometery will
tell you it will not be 1" and it will not be 2". It will be somewhere
inbetween. You can go out and measure the angle of the shackle
(compared to the frame) and figure out the difference in height before
and after (with a little error margin for the change in angle with the
new shackle)(it won't be much).
Scott
- --
*****************************************************
Scott Wilson TLCA #5261
88 4Runner SR5 V6
Santa Clara, CA
http://users.uniserve.com/~rcomber/scottw/scottw.htm
------------------------------
Date: Thu, 17 Apr 1997 15:57:22 -0700 (PDT)
From: Jonathan Albrecht
Subject: shackle length v. lift heigth
To: Toy4x4@tlca.org
> > I think we both agree on everything 'cept for this last comment. I still
> > feel that if the truck is 1" higher, and the shackle is 2" longer, then
> > the bottom of it will be 1" lower than before.
> >
> I haven't really been following this thread, but...simple geometery will
> tell you it will not be 1" and it will not be 2". It will be somewhere
> inbetween. You can go out and measure the angle of the shackle
Yeah, you're right, it's just easier to say 1" and 1", instead of going to
decimal places and stuff. It's the same general concept, regardless of
whether a 2" shackle give 1/2" of lift or 1.9" of lift. This stuff has to
do with how far the axle is from the front spring mount, and how far away
the shackle mount is from the front spring mount. So, actually the exact
numbers will differ between '88 and '89 trucks even.
__
Jonathan Albrecht
albr9619@uidaho.edu
http://www.uidaho.edu/~albr9619/
------------------------------
Date: 17 Apr 1997 09:28:15 -0700
From: "Jay Kopycinski"
Subject: shackles and procomp 85 4RU
To: "Toyota 4x4 List"
Subject: Time: 9:20 AM
OFFICE MEMO shackles and procomp 85 4RU Date: 4/17/97
Jonathan Albrecht wrote:
>I'm not sure. If you lengthen the shackle, then the truck raises up about
>1/2 the additional length of the shackle. And the shackle (and end of the
>spring) are 1/2 the additional length of the shackle lower than before.
>Right?
>
>I figure 2" longer shackle raises frame about 1" higher. So the end of
>the shackle, being 2" longer will sit 1" lower.
Jonathan, you are absolutely right. I goofed. Had to draw it out on paper
to see the effect. It just wasn't getting thru my head. Sorry for any
confusion I may have caused.
_______________________________________
Jay Kopycinski '85 Toylet (ROKTOY)
Gilbert, AZ
ryna10@email.sps.mot.com
http://www.netzone.com/~jayk
Arizona Lo-Rangers 4WD Club TLCA #3243
_______________________________________
------------------------------
------------------------------
Date: Fri, 18 Apr 1997 09:51:20 -0400 (EDT)
From: DRM033@aol.com
Subject: shackle length v. lift heigth
To: Toy4x4@tlca.org
In a message dated 97-04-18 04:46:59 EDT, you write:
> I think this kinda depends upon a lot of things. Usually my reciever
> hitch would hit before my 2.5" longer shackles would. If I drove off a
> ledge though, the shackle would hit (and drag) and then the reciever would
> hit (and drag). I guess the lower shackles never really caused any
> problems even when they did drag...though it could if you tried to back up
> on a steep ledge (where the ledge was below the bumper, but above the
> shackle).
Well, most likely, a ledge like the one you describe would have bashed your
tranny plaet when you went over it in the first place.
Someone else said something about the 1" & 1" & 2" figures. I believe that
Jonathan and myself are using these specific numbers strictly for our
discussion, not actual height.
> I think we both agree on everything 'cept for this last comment. I still
> feel that if the truck is 1" higher, and the shackle is 2" longer, then
> the bottom of it will be 1" lower than before.
>
> I wouldn't say that the 1" lift would cancel the 1" lower shackle but
> rather because of the 1" lift, the bottom of the 2" longer shackle is
> only 1" lower.
>
> Here's a better solution--could someone with extended shackles measure the
> distance from the bottom of your shackle to the ground, and then measure
> the distance from the bottom of the shackle on a similar year, similarly
> set up truck (with stock shackles)?
> __
> Jonathan Albrecht
I will agree, this is getting old. I pomise no more from me on this one.
This clearance issue is really not important. Like I said, If the shackle
does not cross the line between the lowest rear angle and the departure point
of the tire, then it is not interfering with departure angle. I believe the
original thread was in reference to departure angle. Yes, the ledge theory
is true, but you could go all day on that line of thought. I mean, I could
say that since I have 4" blocks, I could clear a bigger "ledge" than someone
with lift springs. Anyway, the spring and shackle should give.
As for backing up, why? If you ha a problem going forward, you will have a
problen going bachward. Adlust for this and continue.
Life is a game of give and take. If putting a shackle lift on changes
clearance, that that is the way it is. (like 1" really matters in this
scenario)
David
DRM033@aol.com
------------------------------
------------------------------
Date: Sun, 20 Apr 1997 20:02:03 -0700 (PDT)
From: Stam Stam
Subject: Shackle pros/cons
To: Toy4x4@tlca.org
I was wondering if a modest shackle lift ( ~ 2in shackle) would do any
good for wheel travel. Perhaps better cramming and extension? What
would it do for hard cornering though? Does anybody have any experiance
with this?
Stamati
------------------------------
Date: Sun, 20 Apr 1997 19:57:39 -0700
From: Scott Wilson
Subject: Shackle pros/cons
To: Toy4x4@tlca.org
Stam Stam wrote:
>
> I was wondering if a modest shackle lift ( ~ 2in shackle) would do any
> good for wheel travel. Perhaps better cramming and extension? What
> would it do for hard cornering though? Does anybody have any experiance
> with this?
>
Been there, done that. I have a 3" longer than stock shackle, which
gave me exactly a 2" lift, on my 88 4Runner. You won't really be
looking at any increased articulation (to my knowledge) unless you're
currently limited by space in the wheel wells. As far as cornering, you
shouldn't notice any changes. Even thought the new shackle is longer,
it will have a welded brace in the middle (stock shackles don't have
this) that will provide extra strength.
If you'd like it to ride better (in my opinion) and definately corner
better, you may want to spend the extra $20 and get poly urethane
bushings for the rear springs. After all, you'll have to take apart the
shackle end of the spring to put the new shackle on anyway, why not go
the whole distance, undo the other end of the spring and go poly. If
you end up doing this, drop me a line, I've got a couple of time saving
tips I picked up while I was doing mine last year.
Scott
- --
Scott A. Wilson __o __o __o __o
Santa Clara, CA _'\<,_ _'\<,_ _'\<,_ _'\<,_
swilson@pacbell.net (_)' (_) (_)' (_) (_)' (_) (_)' (_)
http://users.uniserve.com/~rcomber/scottw/scottw.htm
------------------------------
------------------------------
Date: Mon, 21 Apr 1997 11:31:14 -0500
From: Jack Alford
Subject: Shackle pros/cons
To: toy4x4@tlca.org
Stam wrote:
>I was wondering if a modest shackle lift ( ~ 2in shackle) would do any
>good for wheel travel. Perhaps better cramming and extension? What
>would it do for hard cornering though? Does anybody have any experiance
>with this?
Whether or not you'll get any more wheel travel out of a shackle lift
depends on what your current shackle angle is and how long a shackle you
want to go to. The more that a shackle is kicked back at an angle the
more droop it will give you. If the shackle is near vertical it cannot
droop near as much because it (the shackle) does not have as far to
travel before it reaches the point to where it is being pulled by the spring.
All that said, generally adding a longer shackle will take away from droop
ability a bit because it decreases the angle of the shackle.
Also, generally speaking increasing shackle length without moving the shackle
mount forward (towards the axle) will increase the rate of the spring pack.
Cornering: This will depend again on how long the shackles are and whether
or not you make them braced or not.
- jack
------------------------------
------------------------------
Date: 21 Apr 1997 11:01:12 -0700
From: "Jay Kopycinski"
Subject: Tired of dragging butt
To: "John Skaggs" ,
Subject: Time: 10:18 AM
OFFICE MEMO Tired of dragging butt Date: 4/21/97
john skaggs wrote:
>Jay,
>I am sorry but I wasn't listening when you gave the dimensions of your custom
>shackles. Will they work with stock suspension? I am tired of DRAGGING my
>4Runner butt through ditches and down cliffs. I have had to bend my bumper
>back down to many times and I would like to lift the rear. I looked on your
>web page and didn't see any info there.
I made my last ones from 2" x 3/8" flat bar. They are unbraced but
I did drilled a set of 1/2" holes in them to add a brace later if I want.
The brace would consist of a 1/2" bolt, nyloc nut and a piece of tube
to fit between the two bars.
Stock shackles are about 3.5" eye-to-eye. Mine are now 7.5" or 4" longer
than stock. HOWEVER, just adding 4" longer shackles will probably pitch
your pinion fairly high, unless you compensate with shims. My forward
mounts have been dropped almost 2" so my pinion angle has been kept
fairly low.
I ran 2.5" longer shackles with my old Downey springs for years without
problems.
_______________________________________
Jay Kopycinski '85 Toylet (ROKTOY)
Gilbert, AZ
ryna10@email.sps.mot.com
http://www.netzone.com/~jayk
Arizona Lo-Rangers 4WD Club TLCA #3243
_______________________________________
------------------------------
------------------------------
Date: 23 Apr 1997 12:14:02 -0700
From: "Jay Kopycinski"
Subject: Shackle Angles
To: "Toyota 4x4 List"
Subject: Time: 9:35 AM
OFFICE MEMO Shackle Angles Date: 4/23/97
"Brian Gallus" wrote:
> All this talk about shackles is making me wonder.... What is the
> perfect angle for a shackle to be at when the truck is at rest. If
> there is not an easy generic answer, what variables are involved and
> how does one goe about calculating the correct angle for his/her
> particular vehicle????
I think there is a fairly wide range of angle you can have your shackle
and still have the suspension work ok. A few points though.........
The angle of the shackle helps play some part in the spring rate of
your suspension. If the shackle is standing near vertical, the effective
spring rate will be slightly higher than if the shackle is leaning over
quite a ways.
The shackle angle can also affect the amount of droop you get out of
your springs. If the shackle is near vertical, the axle cannot droop as
far as if the shackle were at more of an angle.
Unless you change or move mounts, the shackle angle you end up with
is pretty much dependent on the spring length you are provided with.
Some kits use springs that are actually shorter than optimal. This
causes the shackle to stand too near vertical resulting in some of the
drawbacks listed above.
To see how your shackles work, you may want to cycle the suspension
from full compression to full droop and see what the shackle is doing
and whether or not it is a limiting factor in your travel.
Hope this helps answer some of your questions.
_______________________________________
Jay Kopycinski '85 Toylet (ROKTOY)
Gilbert, AZ
ryna10@email.sps.mot.com
http://www.netzone.com/~jayk
Arizona Lo-Rangers 4WD Club TLCA #3243
_______________________________________
------------------------------
------------------------------
Date: Thu, 01 May 1997 16:37:49 -0800 (PST)
From: PSHENG@SCUACC.SCU.EDU
Subject: SAGGING '86 4RUNNER!!!!!!!!!!!!!!!!!!
To: toy4x4@tlca.org
The best way to lift that sucker is replact the springs, but
it'll set you back about $200. If you're poverty-stricken like
me, go down to your local 4 wheel parts wholesalers and get some
extended shackles for $27 bucks (the generic ones, conn-ferrs'll
be more expensive) I did this on my '85 (thanx to Scott W for helping)
and it took care of the problem in 1 hr. 15 minutes flat. Best 27
bucks you could possibly spend on your truck. You may have to re-route
your exhaust pipe to clear the shackles (30 bux at a muffler shop), but
it's still worth it.
------------------------------
Date: Thu, 1 May 1997 16:50:04 -0700
From: Eric Johnson
Subject: SAGGING '86 4RUNNER!!!!!!!!!!!!!!!!!!
To: "'Toy4x4@tlca.org'"
PSHENG@SCUACC.SCU.EDU wrote:
> The best way to lift that sucker is replact the springs, but
> it'll set you back about $200. If you're poverty-stricken like
> me, go down to your local 4 wheel parts wholesalers and get some
> extended shackles for $27 bucks (the generic ones, conn-ferrs'll
> be more expensive) I did this on my '85 (thanx to Scott W for helping)
> and it took care of the problem in 1 hr. 15 minutes flat. Best 27
> bucks you could possibly spend on your truck. You may have to re-route
> your exhaust pipe to clear the shackles (30 bux at a muffler shop), but
> it's still worth it.
Being the cheap skate I am, I figured a cheaper quicker way of dealing with
the exhaust issue: get some longer exhaust hangers and lower the rear of
your exhaust system a bit... but I am planning on getting a new exhaust
system soon and will route the exhaust above the spring this time to
protect it.
- --
- -- ej@blarg.net
------------------------------
Date: Thu, 01 May 1997 20:26:44 -0500
From: Todd Hornsby
Subject: SAGGING '86 4RUNNER!!!!!!!!!!!!!!!!!!
To: Toy4x4@tlca.org
At 04:37 PM 5/1/97 -0800, you wrote:
>it'll set you back about $200. If you're poverty-stricken like
Another cheapo route is to have leaf springs re-sprung at a local shop.
Call around maybe there is some place local. I haven't looked into this in
years and don't know if they do it anymore. I doubt if it's expensive though.
Saludos,
Todd
________________________________________________________________________
- -Todd Hornsby (San Antonio, TX) http://www.texas.net/~toddh
- -toddh@texas.net alt: thornsby@alumni.cs.colorado.edu
------------------------------
------------------------------
Date: Sat, 10 May 1997 23:05:55 -0400 (EDT)
From: DRM033@aol.com
Subject: shackles
To: Toy4x4@tlca.org
I was thinking....
How about some 2 piece shackles? They would angle back towards the rear,
then at a pivot, go back to the spring eye. Using stops to limit movement,
the would sit at normal height at rest and extend to almost straight when
drooping.
extended:
O
\
\
O
/
/
O
Compressed:
O____
O
/
/
O
Sorry those are so poor. Anyway, how does this sound? Stupid? Possible?
David
DRM033@aol.com
------------------------------
------------------------------
Date: 12 May 1997 14:24:28 -0700
From: "Jay Kopycinski"
Subject: shackles
To: "Toyota 4x4 List"
Subject: Time: 10:56 AM
OFFICE MEMO shackles Date: 5/12/97
DRM033@aol.com wrote:
>How about some 2 piece shackles? They would angle back towards the rear,
>then at a pivot, go back to the spring eye. Using stops to limit movement,
>the would sit at normal height at rest and extend to almost straight when
>drooping.
snip drawings of two-piece shackle..........
I have seen these used on sevaral vehicles. They look really cool in
action due to all the increased droop, but I'm not sure how effective
they are because they are not under any spring tension.
One consequence of this mod is that it does pitch the pinion angle
when drooping. How much it pitches it depends on your spring and
shackle lengths.
________________________________________
Jay Kopycinski '85 Toylet (ROKTOY) '91 4Runner
Gilbert, AZ
ryna10@email.sps.mot.com
http://www.netzone.com/~jayk
Arizona Lo-Rangers 4WD Club TLCA #3243
________________________________________
------------------------------
------------------------------
Date: Wed, 24 Sep 1997 16:10:17 -0700
From: Eric Johnson
Subject: Shackle slop?!?!?
To: "'toy4x4@tlca.org'"
keith@xgate.columbiasc.ncr.com wrote:
>I would go with the 1" blocks. This will probably mean longer (new)
>u-bolts, but I think it will help maintain the ride. Longer shackles add
>more flex (slop) in the rear springs.
Wait a sec. How do longer shackles add 'slop'? Not a flame, just a
question. And don't we want more flex in an off-road vehicle? Maybe one
man's articulation is another's slop...
I really like shackles. Shackles are my favorite way to do a small rear
lift, because unlike blocks, they still allow full compression, yet they
allow much more extension (the full added length, because they're vertical
when fully extended). Unlike add-a-leafs, they don't give a firmer ride.
Unlike new springs, they're cheap. I've not noticed anything that I'd call
slop in mine. In fact, now I can usually completely stuff one wheel in the
wheel well while the other is almost entirely below the body. You can't do
that with any of the other usual methods.
- -- ej@off-road.com http://www.off-road.com/~ej
------------------------------
Date: Wed, 24 Sep 1997 21:36:19 -0400 (EDT)
From: DRM033@aol.com
Subject: Shackle slop?!?!?
To: Toy4x4@off-road.com
In a message dated 97-09-24 19:23:26 EDT, you write:
>
> I really like shackles. Shackles are my favorite way to do a small rear
> lift, because unlike blocks, they still allow full compression,
blocks do not limit compression. The addition of larger tires and extended
bump stops will limit compression. Actually, full travel should be better.
I see it this way:
Add 2" blocks with stock tires. The compression should be the same, and the
travel at the tire should be about 2" more. Since the spring only extends so
far, you are adding 2" to that. This sound right to anyone else?
David
DRM033@aol.com
------------------------------
------------------------------
Date: Sun, 9 Nov 1997 18:42:32 -0800
From: "Raymond Kumar"
Subject: shackles
To: "Toyota 4x4 Digest"
My 85 runner w/Downey lift has sagged a bit not so much from wheeling but
from the many accesories on the rig(arb bumper,rear bumper w/spare
carrier,roof rack etc.)I was wondering if anyone has experienced any
driveability problems associated with longer shackles or should I just
rearch and add-a-leaf.Any suggestions would be appreciated.Ray
------------------------------
Date: Sun, 9 Nov 1997 20:38:37 -0800 (PST)
From: Chris Geiger
Subject: shackles
To: Toy4x4@tlca.org
I have used shackles that were 1" and 2" longer than stock on other trucks
I have owned, they worked fine for me to add a little lift, but I found in
time that the leaf springs would bent back to the point I was before I
added the shackles. Scott Wilson has been using the new soft add a leaf
and last I heard he was happy with how it was working.
Chris Geiger 93 4Runner http://geiger.mcl.ucsb.edu/offroad.html
> My 85 runner w/Downey lift has sagged a bit not so much from wheeling but
> from the many accesories on the rig(arb bumper,rear bumper w/spare
> carrier,roof rack etc.)I was wondering if anyone has experienced any
> driveability problems associated with longer shackles or should I just
> rearch and add-a-leaf.Any suggestions would be appreciated.Ray
>
>
------------------------------
Date: Sun, 09 Nov 1997 21:15:02 -0800
From: Brandon Miller
Subject: shackles
To: Toy4x4@tlca.org
Like any other lift, driveshaft length needs to be considered. The
pinion angle caused by the shackles also needs to be considered. The
effect isn't bad in the rear but in the front it is enough to make your
driveshaft fall out under full drop and enough to make it necseeary to
use shims to correct the pinion angle. I got full size Con-Fers front
and back and love em' but I did have to modify the driveshaft and use
shims. My "adjustable" torque rod is also too short now (damn thing is
stuck and won't adjust), guess that just made up my mind on wether or
not to run the torque rod.
- --
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Brandon Miller email: sac78483@saclink.csus.edu
Sacramento, CA millerb@gaia.ecs.csus.edu
url:
http://gaia.ecs.csus.edu/~millerb
TLCA #6013
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
------------------------------
------------------------------
Date: Mon, 10 Nov 1997 08:38:11 -0800
From: Barney McNamara
Subject: shackles
To: Toy4x4@tlca.org
My truck came with 3" longer Confer shackles on it. It gives me about
1 1/2" lift front and rear. I think they improve the articulation, though
I've never tried to measure it and compare with stock. I like the way
the truck goes over rocks and ruts, and have been through a few trails
that looked bad but gave me no trouble. I have had some problems with
rear shaft u-joints, but have no shims or other adjustments. The front
driveshaft seems OK - it hasn't fallen apart. I did have to put in a
longer torque rod, and extended bolts for the sway bar - I like them
both because of my mountain-highway commute. The alignment is off a bit
in camber and caster - and can't be fixed, they tell me. But my tire
wear is even, and it doesn't pull too hard to the side (a little to the
right, but not bad.)
______________________________________________________________
Barney McNamara JENNY - 83 Toyota Short Bed
( barney@flowpoint.com ) stock 22R motor ; 3" body lift
Santa Cruz, Ca. 8" alloy rims; 31" BFG A/Ts
homepage: http://www.scruz.net/~barneym/barnhome.htm
______________________________________________________________
------------------------------
Date: Mon, 10 Nov 1997 09:18:17 -0800
From: Brandon Miller
Subject: shackles
To: Toy4x4@tlca.org
> The alignment is off a bit
> in camber and caster - and can't be fixed, they tell me.
I forget which is which but you can correct one of em with shims, and
the other shouldn't be out. You can't correct the in/out aspect of the
wheel but it shouldn't be out of spec either unless something is wrong.
My truck is within specs with a Trailmaster 4" lift and 3" over stock
shackles, and axle shims in the front only.
- --
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Brandon Miller email: sac78483@saclink.csus.edu
Sacramento, CA millerb@gaia.ecs.csus.edu
url:
http://gaia.ecs.csus.edu/~millerb
TLCA #6013
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
------------------------------
------------------------------
Date: Thu, 20 Nov 1997 22:49:07 -0800
From: "Kenneth Sigel"
Subject: Wheel Travel
To:
I'm not sure how much travel a stock straight axle Toyota should have, but
if you add shackles, you'll see a large improvement. I'd guess that will
just the longer shackles, you'd see at least 10" of travel -- make sure
you're not bottoming out on the stock shocks.
------------------------------
------------------------------
Date: Thu, 22 Jan 1998 11:00:21 -0800
From: "wg"
Subject: Ford shock mounts and longer shackles
To:
Darren Floen wrote
> Hey everyone,I need some longer front shackles for my 85 Toy.I am
> wondering who sells a complete kit with bolts and bushings.I'm looking
> for 2" longer reinforced shackles.Who's got the best price?If the price
> is right i may buy them instead of fabbing them.
If your looking for 2" longer front shackles I don't think they exist
commercially? What I did was just take the Confer front shackles
and cut the center out of them and drilled the springeye mounting hole
1" higher (confers are 3" longer than stock). It works great this way
and gave me an extra inch of lift..instead of 2"
They come with the bolts but not the bushings. Just get some
of the black Energy Suspension bushings..they are quite soft.
Also I'm from Canada too and the best price I could find for the
Confer shackles was between $75-80!
> Also,i want to extend my front shock mounts,and i may fab my own but i
> was thinking about the ford shock mount swap.What is the exact model
> that i need(F250-F350,2wd or 4wd)?
On my truck I fabricated the extended front shock mounts.
What a huge waste of time and effort!!!!!!!!
Just get the Ford mounts from a wrecker.
Ford f-250 and 350 front upper shock mounts are bolt on.
If you look in the wheel well of a ford 4x4 you will see how long
they are and perfect for 9012's!
Wil
81Toy
http://www.off-road.com/~irc/
------------------------------
------------------------------
Date: Tue, 27 Jan 1998 08:40:58 -0500
From: Sheldon Gardner
Subject: Downey Shackles
To: Toy4x4@tlca.org
> Date: Mon, 26 Jan 1998 17:02:19 MDT -0600
> From: ggibb@msu.oscs.montana.edu
> Subject: DOWNEY RUBICON SHACKLES?
> To: Toy4x4@tlca.org
>
> HAS ANY ONE TRIED THE DOWNEY RUBICON SHACKLES ON THE FRONT OF A SOLID FRONT
> AXLE TRUCK? (I HAVE AM 85' TRUCK WIHT 3" SOFT RIDE SPRINGS.) WHAT DID YOU
> THINK? WAS AXLE ARTICULATION IMPROVED? DID THEY LIFT THE TRUCK? DID THEY
> EFFECT THE RIDE? I'M NOT LIKING FOR LIFT JUST A SLIGHT IMPROVEMENT IN RIDE
> AND AXLE ARTICULATION, IF ANYONE HAS ANY THOUGHTS ON THIS PRODUCT PLEASE
> LET ME KNOW.
> GEOFF GIBB
> BOZEMAN, MT
> TLCA # 5434
>
>
I have the 3 inches soft ride and 3 inch Downey shackle and will tell you
about my experience. The shackle is fine and works good you will probably
need to use shims in front get get the pinion up but it's no biggie. My only
problem was the Soft ride springs have a short second leaf ; with the 3"
shackle it caused the main leaf to kink slightly where the second leaf ended.
I got a pair of Toy rear springs from the junkyard last weekend and am
planning on using a leaf inserting into the soft ride spring pack, I'm
hopeful that this will cure the problem for now. I never took out the
overload leaf with the soft rides. I'm guessing that if I had my springs
would never had kinked at all but would probably have sagged a lot quicker.
Hope this helps
Sheldon
sgarD@flnet.com
------------------------------
------------------------------
Date: Wed, 25 Feb 1998 07:38:47 -0800
From: Dan Merrick
Subject: Shackle questions
To: Toy4x4@tlca.org
Ken:
I have ConFer(sp?) shackles on my '85 Toyota. They claim that the front
ones provide 2" of lift(4" longer than stock) and the back ones provide 1
5/8" of lift(about 3" longer than stock). You may want to call them, as I
bought mine about 6 years ago. I believe they have a variety of lengths
available. I don't have any trouble with the shackle hitting the exhaust,
but my truck is a short bed. I don't know if my shock arrangement is
different than yours. The longer shackles angle back much more than stock,
so unless you have some extreme droop in your suspension, I'd guess it
won't hit your exhaust. You may also want to take some measurements to be
sure the shocks you use are long enough. I broke a couple of RS 5000's when
I first got the shackles due to improper length. You may need to adjust the
bump stops, I know my suspension never even touches the bump stops because
of the shackles. This can be trouble if you are hard on your truck(jumps,
rock crawling, etc)
Let me know how it all works when you are done!
Dan M
>------------------------------
>Hi all,
>Would someone remind me what the general rule of thumb is regarding
>shackle length and increase in ride height? (Something like a 2"
>longer shackle will lift the truck about 1.25"???)
>
>My Xtra Cab is starting to get that saggy butt look. I want to
>raise the rear about 1", any recommendations on shackles?
>
>Also, when my rear springs are at full droop, the stock shackles are
>almost straight up and down. If the shackle were to travel forward
>another 20 degrees from straight up and down, it would hit my exhaust.
>I wouldn't expect it to hit with the longer shackles and stock shocks,
>but installing longer shocks that increase my travel might allow it
>to travel this far forward and hit my exhaust?????
>
>As always, thanks,
>Ken Emanuel
>
-------------------------
------------------------------
Date: Sat, 14 Mar 1998 22:32:32 EST
From: "james stevenson"
Subject: homemade shackles
To: Toy4x4@tlca.org
>I'm only going to make them long enough to get about 2 inches of lift.
That's a lot of lift (4 in longer) to do with shackles. I don't know
about your laws but lust putting on the shackles will be dangerous.
Longer shackles are only needed when longer travel is employed. Why no
cut it back to a 1in lift and remount the hangers below the frame. As
for the shackle the more bracing and the thicker the shackle the better.
Relocating the hanger will give 1.5 in lift and more shackle travel.
James Stevenson (TonkaTuf)
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
------------------------------
Date: Sat, 14 Mar 1998 11:55:26 -0800 (PST)
From: Luke P Miller
Subject: homemade shackles
To: Toy4x4@tlca.org
I'm using unbraced shackles that are two inches longer than stock, made
with 3/8" flat bar. They allow a good bit of misalignment when twisted up,
and haven't failed on me yet. But, I tend to agree with Mr. Stevenson in
this case. Bracing those shackles would seem to be safer, if they're
going to be that long. Hypocritical?
Yep, but somehow I justify it to myself...
Luke Miller
__________________________________________________________________________
1985 4Runner 3"Alcan front lift, 3" custom Mazda spring rear lift, 4.88's,
rear lockright, RS 9000's, 32x11.50 Michelins, ugly homemade bumpers (the
best kind)...
__________________________________________________________________________
------------------------------
------------------------------
Date: Sat, 14 Mar 1998 18:32:31 -0500
From: Darren Floen
Subject: homemade shackles
To: Toy4x4@tlca.org
I made my own shackles from 2"x5/16" flat stock.They are unbraced.I
built them 2" longer than stock.I used 3/4" bolts,wich are 1mm larger
than stock.That worked good because my bushings were a little loose,and
that tightened them up.
On the front,i bent the shackles by cutting slits across the
shackle,and then heating them with a torch.I then welded up the slits
with my mig.
Darren
------------------------------
------------------------------
Date: Tue, 17 Mar 1998 05:17:49 EST
From: "james stevenson"
Subject: Double jointed shackle set up / Mazda spring swap??
To: Toy4x4@tlca.org
>James I see what you are trying to say, but I still see no real
>life advantage to such a setup.
I must be missing what you are getting at. I haven't done the Longer
spring/Double shackle. I have longer springs (custom made) with a
shackle on each end. One of these shackles is a dual setup. This started
as an aspect of that setup but is also a valid setup. It seems that you
thinking is in terms of a Tension Shackle not a compression shackle. The
lowly shackle has more affect on suspension and steering than most
people realise and is often overlooked. I'll try to keep this simple as
possible as the shackle is actually more complex than most people think
and can get overly technical. Lets start with the various shackle
designs and what they do then I'll try to answer your questions. .
First there are two types of shackles Compression and tension. A tension
shackle is one you would see on a full size rig like a Blazer. With this
type you see the spring eye above the shackle bracket, the weight of the
frame pulls down on the shackle which pulls down on the spring. A
compression shackle is what you see under a Toyota pickup. With this
type, the weight of the frame rests on the shackle or to think of it
another way the shackle is being pushed up onto the frame due to the
weight of the frame. This push will become pull only when the wheel
leaves the ground and the frame suspends the weight of the suspension.
I won't get into the geometry of this but the angle of the shackle to
the frame plays a big part in the spring rate, axle loads and forced
articulation. Forced articulation in this context is the leverage
applied to the opposing spring pack. This force causes an opposite
movement on the opposing spring pack. As spring rate increases, more
force is needed to move the spring. These additional forces are applied
directly to the diff housing which creates more stress on the welded
tubes which is a common cause of housing breakage. With the vehicle at
rest , the closer to vertical that the shackle is, the greater the
effective spring rate. This is due to the angular movement of the spring
eye along the arc of the shackle. With the shackle vertical the spring
has to move the shackle down to expand creating a higher rate. This is
the reason that re-arched springs or add-a-leaves can make the ride
overly harsh and why replacement spring generally have longer main
leaves. As far as articulaton and ride quality are concerned the
optimum shackle length and position is one that allows the spring to
move from a positive arch to a negative arch under full compression
without restriction. With compression shackles, longer shackles add lift
to the vehicle. Lift shackles are usually added for the wrong reasons,
being purely for lift rather than a need for increased angular movement.
In the case of a Toyota Pickup this rotates the axle forward causing
caster and toe in problems. Degree shims can be used to correct this for
mild lifts. The longer the shackle the greater the stress on the frame
and leaf spring eye. A common solution is to add a brace between the
plates. This creates new problems as more force is transferred into the
frame. Generally it is fine for under 1.5 in lift but over that becomes
dangerous. Add to that most designs use a drawbolt which is far weaker
than the stock C pins.
You have probably seen the "Velvet Ride" shackles released by BFG for
full size trucks. These are quite different to a dual shackle and is
commonly referred to as a "Two Piece Design". This is because the
shackle acts as a scissor design. The join between the two pieces of the
shackle incorporates a Rubber torsion spring. The shaft joining the
pieces is not round but a triangular and the mounting for the bush has
been squared off. As the shackle bends, increasing force is applied to
the bush. When the shackle becomes straight a stopper is used to prevent
inversion. In this type of shackle, the bush acts like an overload
spring in reverse. The main or conventional part of the shackle handles
the expansion of the Leaf Pack. The additional part is a load sensing
device. In the situation where you have a high spring rate (rough ride)
and no load, the torsion joint moves to provide suspension travel. It is
not until enough load is applied, that the shackle locks and the leaf
pack begins to expand. This type is valid in both compression and
tension form.
A Dual Shackle not to be confused with a Two Piece Design, is only valid
in Compression form. The dual shackle is divided into two parts, the
main shackle and the pivot shackle. The main shackle is the same part as
in a conventional design and connects to the spring eye. The pivot
shackle attaches to the shackle pad on the frame at one end and the main
shackle at the other. As we dealing with a compression design, under
normal travel the pivot shackle is forced up against the frame and
spring expansion/contraction is taken up by the main shackle. When the
spring pack reaches its full down travel the pivot shackle begins to be
pulled away from the frame by the same forces which creates the forced
articulation. At this point the shackle is still under compression but
the added force of the opposing spring hard up on a bumpstop forces the
pivot away. As load is reduced from the opposing spring the pivot
shackle returns to the normal position. In this type of shackle it is
critical to have the pivot shackle locate on the frame. The common
design is to have the pivot shackle in a U design, which wraps around
the frame and has the leading edges angled away from the frame to
improve the location process. In the case of Toyota front mounts some
material needs to be removed as the mount is inside the frame not below.
The shorter the pivot shackle greater the risk of inversion. A stopper
must be added to prevent this occurring. A double shackle of the same
length as a Lift Shackle exhibits the same angular movement. The
proportion of overall length in the Main/Pivot shackles can be adjusted
to alter spring rate in a two stage progressive manner. Side loads with
a double shackle are at stock levels and the force on the frame is mount
is less than stock as its distributed into the frame as well as the
mount. In comparison to a lift shackle, double shackles are far safer
and are kinder to the mounts than the stock setup. Another benefit is
the ability to install longer springs using the stock spring mounts.
Darren Wrote
>I see no real life advantage to such a setup
I hope you now see some like lower loads on the shackle pads and
increased travel
>What have you done about body roll unweighting the extra shackle?
This is not an issue with a compression shackle but is one of the
reasons why a double shackle will not work in tension form.
>Do you pin them?
No, I assume this question is in relation to normal road use. Under
normal road use little travel is used. How many times to lift a tyre on
the road ? The pivot shackle does not come into the picture until the
tyre would have lifted without the pivot.
>What about sidehill stability?
What about it? If you are referring to side loads on the shackle it's
the same as stock and far less than a lift shackle. If you are talking
about lifted trucks and stability that's another issue entirely and is a
function of track, tyre profile, suspension rates and weight transfer.
>I'll assume you use traction bars, but what type?
No I'm not they restrict travel. I am using a V link to locate the axle
check a few issues back for that one.
>Do you have any pics or sketches scanned that might help
>me to see the light?
Send me a direct e-mail so I can forward some.
>I do see many disadvantages
Is this still the case?
>This is not a flame, just a discussion, btw.
I didn't take it as a flame. Its better if you ask than not understand.
I just wasn't going to go into this much detail unless someone asked.
James Stevenson (TonkaTuf)
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
------------------------------
Date: Mon, 16 Mar 1998 14:42:06 EST
From: DRM033
Subject: Double jointed shackle set up / Mazda spring swap??
To: Toy4x4@tlca.org
In a message dated 98-03-16 13:22:38 EST, you write:
>
> I must be missing what you are getting at. I haven't done the Longer
> spring/Double shackle. I have longer springs (custom made) with a
> shackle on each end. One of these shackles is a dual setup. This started
> as an aspect of that setup but is also a valid setup.
First of all, thanks for the good text on shackles.
The point here is that you have a what seems to be a 3 or 4 link locating
system, which is another ball game.
I too have looked at some of these designs for extreme travel, and I believe
the point he was trying to make is that there gets a point where the extra
travel is negligable for the ammount of work done to produce it.
With the double shackle setup I too think that you get to a point where you do
not have enough weght/force on the drooping tire to allow it to get any
traction. I believe that one of the extreme travel machines in the mags last
year even stated that this was a problem they were dealing with.
It is kinda funny to sit back & see trunds in fourwheeling, which is what this
comes down to. A while back all the mags were raging about mega travel. Then
they come around and start admiting that this was a trund, like everything
else. Sure, I wil say that travel will not go away, but I think that for the
majority of the people that go off road (even serious trails) that extra 1/2"
of travel will never be noticed of missed.
Look at the Top Truck Challenge. Did a small, rock crawling type truck win?
Did the mega travel trucks steal the show? I personally think the old Blazer
stole the show, and he had carb problems the whole time.
Back to the double shackle problem...
So, if you can get the tire to stay on the ground, but it spins uselessly with
no real "traction", what has it gained you?
Go ahead, tear holes in this :)
- ---------------------------------------------------------------------
David Moore DRM033@aol.com
90 Toyota Truck - 4" ProComp, 33" Swampers,
4.88's, rear ARB, TJM bumper & Ramsey #8000
TLCA #5662
Traxx In Motion 4 Wheel Drive Club
www.netmatter.com/traxx
- ---------------------------------------------------------------------
------------------------------
------------------------------
Date: Mon, 16 Mar 1998 16:39:14 -0500
From: Darren Floen
Subject: Double jointed shackle set up / Mazda spring swap??
To: Toy4x4@tlca.org
If you are talking about shackles at each end of the leaf spring,then i
see advantages.If you are talking about two linked shackles at on end of
the spring,i see few advantages and many disadvantages.A system like
this might provide a slight increase (slight) in traction,but what about
the fact that the spring is no longer positively located to the
frame?There would have to be an increase in sway,unless the link resting
on the frame was pinned down.I see what you are trying to say about
leverage from opposing springs and such,but if that is such a big
concern just use a super long spring.Longer springs will wrap easier but
you are already using some sort of bizzare link system that i assume is
to control this.I am a heavy truck mechanic(apprentice)and the newer air
ride trucks(with the Neway sys.)suffer severe rearend
hop(unloaded)because because the trailing arms that the axles mount to
are not secured at the rear,such as would be the case with buggy springs
and double shackles.The rear axle rotation would try to extend the
shackles under acceleration,just as the front would do in reverse gear.
What is done to combat this?
For me to want this extreme droop,it would have to have full spring
pressure available at the tire,but my steering etc. is already maxed.Do
you use crossover?What type of leaves are you using(brand-custom)?
Darren
------------------------------
------------------------------
Date: Tue, 17 Mar 1998 12:27:29 EST
From: "james stevenson"
Subject: Double jointed shackle set up / Mazda spring swap??
To: Toy4x4@tlca.org
>The point here is that you have a what seems to be a 3 or 4 link
> locating system, which is another ball game.
My springs run on a 4 link. In terms of double shackles with one fixed
mount the engineering is the same
>that extra 1/2" of travel will never be noticed of missed.
It's a lot more than M-= inch. But depends on the length of the pivot
shackle.
>So, if you can get the tire to stay on the ground, but it spins
>uselessly with no real "traction", what has it gained you?
If you compare a rig with single shackles and take it to the point that
a tyre lifts then add double shackles and try again. You will find you
are not spinning the tyre at the same point in travel. Eventually you
will be in the same situation but this 4+ inches down
>If you are talking about shackles at each end of the leaf spring,
>then I see advantages. If you are talking about two linked shackles
> at on end of the spring, I see few advantages and many >Disadvantages.
It is true that shackles on both ends is a better system with more
travel.
>A system like this might provide a slight increase (slight) in
traction,
At the extremes of travel no traction is gained. At a point where extra
travel is in operation more traction is present.
>what about the fact that the spring is no longer positively located
>to the frame?
It is, I'll send you the pics that will help.
>There would have to be an increase in sway, unless the link resting
>on the frame was pinned down.
That depends on the pivot shackle design and mount. I convert the stock
mount to a bearing drive and the shackle itself locks into the frame
under normal travel.
>I see what you are trying to say about leverage from opposing
>springs and such, but if that is such a big concern just use a super
> long spring.
The length of the spring has little bearing on forced articulation.
>Longer springs will wrap easier but you are already using some sort
>of bizarre link system that I assume is to control this.
The wrapup is a function of the spring rate. When adding longer springs
most go for lesser rates and a linkage to control induced wrapup. With
shackles on both ends I go for a V link. With a shackle on one end I
stay away from linkages but use a higher spring rate, often with a V
link with quick disconnects for the trail. I don't think a V link is
bizarre
>newer air ride trucks suffer severe rearend hop(unloaded)because
>because the trailing arms that the axles mount to are not secured at
> the rear, such as would be the case with buggy springs and double
> shackles. The rear axle rotation would try to extend the shackles
> under acceleration, just as the front would do in reverse gear. What
> is done to combat this?
The axle hop is caused by the spring rate not the links. If the rate is
too high as in unladen this is the only thing the axle can do. . On a
tension shackle such as the "velvet ride" shackle, addresses wrapup
effectively due to the torsion effect. As I said in my last post I'm not
a fan of buggy springs due to the stresses. Buggy springs go on the
fixed eye which puts them under compression during wrapup. With Double
shackles on the trailing edge, wrapup is per stock and is a function of
the spring rate. Wrapup will cause the main shackle to move not the
pivot shackle
>Do you use crossover?
I'm using a double pivot crossover setup.
>What type of leaves are you using(brand-custom)?
I use Superlift a lot but my springs are custom made.
James Stevenson (TonkaTuf)
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
------------------------------
------------------------------
Date: Fri, 10 Apr 1998 15:42:51 -0500
From: Jack Alford
Subject: Re: rear blocks
>works. I would be willing to be that ad-a-leaves would reduce my present
>articulation. I may get a set of slightly longer shackles to see if they
>really do increase travel.
A set of longer shackles alone will not really increase travel. Think of
how a set of longer shackles will decrease your shackle angle (from
leaning back less). Some perceived articulation might be gained from the
extra ride height gained from longer shackles but more travel from shackles
doesn't really happen. It might allow a slightly longer arc range since the
shackle will be longer but minimal at best in my experience. Unless you
go to some really long shackles like the 7" center-to-center ones I have
but I use them in conjunction with springs that are longer which allow the
shackle to still be kicked back and not standing straight up.
- jack
============================================================================
Toyota 4x4 page: http://www.off-road.com/4x4web/toyota
------------------------------
------------------------------
Date: Sat, 11 Apr 1998 06:46:43 -0600 (MDT)
From: Scott Ellinger
Subject: Re: rear blocks
> ok then, that agrees with everything I thought, but is contrary to the popular
> thought on the list. I keep hearing people say shackles increase articulation
> better than blocks, but I have always failed to see how you could gain much.
> Even longer shackles could not help me easily get to 4" of lift & still flex
> well.
I'll try.
However, this gets a little complicated, so I'll try to avoid referencing ride
height too often, because it's mostly irrelevant, except for determining how
much of your travel is compression vs. droop.
Here goes....
Imagine a stock truck with no lift at all. At a certain location, the axle
makes contact with the frame (bottom out) and can compress no more.
At a set distance (drooping down) from that bottom out point, it "tops out"
and can droop no more. This usually happens at about the point at which the
shackle and spring are in line, assuming that there are no other limitations.
Now take that stock "top out" point, and allow about another inch or so of
droop into the equation, by lengthening the shackle. The spring can now arch
a little bit higher before the longer shackle is in line with it, thus
allowing a little more travel than before.
There's a catch here, though. If the spring was limiting compression more
than the bottom-out point on the frame, it will continue to do so; you will
have the same travel as before, but in a different location, slightly farther
from the frame.
If, however, the spring can flex farther, then you can utilize all the travel
from your old bottom out point, down to your new top out point, which,
depending on how tall a shackle lift you've installed, could be as much as
two or more inches below where it was before.
More catches to the explanation: this assumes that your shocks, U-joints,
brake line(s) etc. can take this increase, and that other side benefits don't
interfere. I'll get into "side benefits" below.... :)
>
> After looking at all the info I have come across, I still see that my 3.5"
> rear blocks with stock springs (overload leaf still there) flex extremely
> well. A torque bar would get rid of the only problem I have come across -
> which is axle wrap. I also like how the springs ar up higher & out of the
> way. If my springs start to sag - a set of used stock springs are way cheaper
> that new lift springs. I just can't figure out why people keep saying blocks
> are so bad. If someone has some input on this please reply.
My personal experience is with originally a four-cylinder, 35's, and a Trail
Master suspension system (with 3" rear blocks). I wrapped up those rear
springs so badly that there is a noticeable "S" shape to them when they are
on a truck, and visible warped areas (to me, anyway, since I know where to
look for it) on the springs now that they're off the truck.
I will readily admit that I abused that suspension setup (and continue to do
so, but it's a different suspension in many ways now) very severely, and even
more so with the V8 swap that I currently run. With well-mannered driving by
conservative drivers on smooth terrain, blocks are not an issue. However,
in the rocks, or if you happen to hop the wheels a little, or in mud, blocks
will quickly end the lives of the rear springs.
>
> I guess I am still looking for someone to convince me to tinker with things,
> but that old "if it ain't broke..." saying keeps popping up.
>
More tinkering--here's the "side benefits" I mentioned above.
With a longer set of shackles, if the bolts and shackle plates are all
separate parts (as in "Downey"'s Rubicon Shackles, which I have) then the
shackle can flex side to side a little when the suspension twists. With
the stock shackle, the pins and shackle plates are locked together very
tightly, and can't allow this twist.
This allows freer and more articulation (a different beast from travel)
in the suspension, which can allow more travel overall. For even more
travel, you can loosen the bolts some so that they get sloppy; this will
allow the most travel possible, but will make for sloppy, unpredictable
handling, and a possibly unsafe vehicle at road speeds.
Then again, if you're like me, you can't drive on the street when you're
aired down to trail pressure (<10psi) anyway, and the time while the tires
are airing up is a perfect time to tighten up those loose shackle bolts.
- --scott
Scott Ellinger ellinger@holly.colostate.edu Larimer County 4WD Club
Visit my Home Page: http://holly.colostate.edu/~ellinger
Please help me make Four Wheeler's Top Truck Challenge '98--vote #28 on
the Top Truck ballot in the May '98 issue of Four Wheeler Magazine!
============================================================================
Toyota 4x4 page: http://www.off-road.com/4x4web/toyota
------------------------------
------------------------------
Date: Thu, 06 Aug 1998 09:26:58 -0700
From: "Jay Kopycinski"
Subject: Lift...3" or 4.5"
Michael Woodruff wrote:
>I'll be purchasing one of two lifts that Superlift makes (3" or 4.5") in a
>week or so. The price between the two is considerable, the 4.5 comes with a
>draglink which isn't needed on the 3. Whats the point of buying the 4.5
>versus the 3 and putting longer shackles with it (much cheaper)
2 inch shackles aren't bad and let you retain flatter springs while still
gaining some lift. Myself and others have found that 3 inch shackles
up front tend to want to ruin springs due to the more drastic spring
angle. Shackles often necessitate adding axle shims to correct the
caster angle.
It depends largely on what you plan to use the truck for.
>It seems I
>recall someone saying that extended shackles improved driveline
>angle's.....is this true??
They will tip the pinion flange down. Shimming the axle will bring this
back up and most often provide a better driveline angle.
> Would the longer draglink that comes with the
>4.5 kit be necessary with a 3" lift and say....1 or 2" longer shackles??
It is a good idea to use it, especially if you plan to crawl the truck.
Jay Kopycinski '85 Toylet (ROKTOY)
============================================================================
Toyota 4x4 page: http://www.off-road.com/4x4web/toyota
Back to the top of this thread
Back to the top of the Suspension Threads Group
Back to the top of the Technical Discussion Groups
Back to the top of the Toy Thread Tree