My CJ7 w/ sprungover wagoneer 7 leafs flexes very well, but the spring wrap necessitates a traction bar. So I get a Sam's Offroad type and can't figure out how to keep it from limiting the flex quite a bit. It is johny jointed at the shackle end. I'm sure someone has figured this out.

If it's a sams style it shouldn't limit travel- what are you doing wrong?

I don't know what I'm doing wrong, hence the question.

What could I be doing wrong? The traction bar isn't exactly complicated.

no, it's not complicated. do you have any pics ?

do you have the shackle mounted such that it's close to vertical ?

- jack

If its installed anything like this, it shouldn't effect travel. Make sure it can rotate at the shackle and that the shackle moves freely:
http://www.fototime.com/ftweb/bin/ft.dll/standard?pictid={CEA51043-7472-4EBB-AB34-94A5B7030B07}

Originally posted by newt
My CJ7 w/ sprungover wagoneer 7 leafs flexes very well, but the spring wrap necessitates a traction bar. So I get a Sam's Offroad type and can't figure out how to keep it from limiting the flex quite a bit. It is johny jointed at the shackle end. I'm sure someone has figured this out.

Hard to tell from this post... Have you installed it yet, and wheeled it and its limiting travel, or are you asking theoretically about it??

It is attached as in the posted picture w/ the only difference being that the frame mount is above the fwd end of the bar. The shackle is close to vertical at normal ride height.
I have not wheeled it yet, but have flexed it by lifting one wheel w/ a fork lift. With the bar there is less flex than without the bar (~3.5' w/ vs ~4' w/out). When the traction bar is not attached at the shackle end, you can see the free end move ~8" vertically when flexing the rear.
I'm hoping that it will loosen up some with use. Also, I understand that there is a difference between using a forklift and real world wheeling.
Any thoughts? I hope to have pictures this weekend.

Sounds like the traction bar isn't allowing the springs to rotate the axle as it cycles, so it's creating a bind that limits travel. After all, that’s what they do. Don't think there is much you can do about it unless you relocate/redesign the spring or bar setup/angles to keep the arcs/angles more similar...

I run a Sam style trac bar and it seems to flex fine for me.
http://www.respite.org/images/cj66dean/soupcan2.jpg

Originally posted by newt
My CJ7 w/ sprungover wagoneer 7 leafs flexes very well, but the spring wrap necessitates a traction bar. So I get a Sam's Offroad type and can't figure out how to keep it from limiting the flex quite a bit. It is johny jointed at the shackle end. I'm sure someone has figured this out.

You need this!!!

http://www.pirate4x4.com/forum/showthread.php?s=&threadid=76968

i would take 6" less travel for having a rear driveshaft that wont fly off from a exploded u-joint. plus it will climb A LOT better without the wrap. way more funtional than the 6" of travel.;)

Yeah, I've got to build one for my rig. I tweaked the @#$% out of my rear F150 packs (mounted backwards) on Upper Helldorado last week end. I have no wheel hop at all, but power application while the rear axle is drooped makes for some strange shaped springs... Bowed way out with the springs all splayed out… Now the main leaf looks like it’s “doing the wave”…

on teh shackle side you HAVE to run a heim joint with the jam nut loose. So the ladder bar can turn on the threads to limit the negative affecton travel.

My rig I run a custom sam's style ladder bar. I lost about .5"-1" of flex, cheap price to pay for being able to hammer down and not hop. :D

I think what you meant is that you HAVE to provide *some* means for the bar to twist as far as the axle can articulate. Be that bushing, loose heim, or other mechanism.

I saw a really cool idea in Moab this week end. The guy had a drive shaft spline welded onto the end of the ladder bar. I think they used a spline for no other reason than to provide for grease. Anyway, the spline fit inside a tube (no matching splines) which was mounted to a simple horizontal spring bushing (roughly 1.5 x3). This allowed easy, (mostly) unrestricted up/down movement of the axle while controlling pinion angle. The spline could move in and out of the female tube as needed for vertical axle travel. And, the spine could rotate in the tube as much as needed for articulation. No shackles, no heims, no JJs, just simple and direct...

you need to have the shakle facing down so the traction bar pulls on it when wrapping...also if shakle is wrong way it will dive the pinon during droop and raise it durring compression..which will bind..

if you have lots of travel you need to run a longer shakle IMO

leaving jamnut loose is also a good idea

Why would the shackle up vs shackle down make a real differance? Pictures and small words would be nice (I'm no suspension engineer). Thanks.

Originally posted by Moab Austin
you need to have the shakle facing down so the traction bar pulls on it when wrapping...also if shakle is wrong way it will dive the pinon during droop and raise it durring compression..which will bind..

if you have lots of travel you need to run a longer shakle IMO

leaving jamnut loose is also a good idea

Think this is backwards.. The rear pinion wants to climb, so shackle should be up if you want the bar pulling on the shackle.

i would think as long as its straight up and down it would make no difference.;)

It shouldn't make any diff. if it is up or down. Yes you do need to allow the bar to move side to side some and that is why I put hiems at all 3 spots or run a shackle that has a center pivot to allow it to twist allong with move in and out.

Pinion movement relative to shackle location is a function of shackle length and location and the arc it describes, combined with the locating arm and the arc it describes, combined with the location of the fixed spring eye relative to the axle with the arcs that they describe, etc. Basically this is a complex system all moving at the same time. Change the shackle length or orientation and it WILL have an effect. Exactly what that effect will be depends on all the other stuff combined.