On this site, you’ll find some information about the anti-wrap bar. The messages are replies from the Jeepoffroad list (JPOR), CDN Jeep list (CDN) and JeepTech list (JP). Send me an email if you need somebody’s email address. I’ll start with the question that I asked to the Jeepers on these lists.

After a nice day off-roading this weekend, I want to report you about my experiences. I'll not exactly describe what I did, because Marc van Rey will make a report of that (or not Marc??).

Let me first start with saying that we (Marc YJ, Reggy YJ, Jan CJ5 and I YJ) off-roaded in very loose sand (like dunes), not much mud (except on my Jeep, don't know where that came from), water and a little bit in the woods (although nobody followed me there). Well, the things that I have experienced here are first that I definitely need an anti-wrap axle bar with my SOA setup. I still have a lot of axle wrap. The springs didn't sag much (with the extra leaf), but the axle wrap came back. Especially when you're digging in the sand, the axle wrap is very bad!!! NOW, I'M LOOKING FOR AN ANTI-WRAP AXLE BAR!!!! I'm looking for a design. I saw the design in Petersen's of November 1997. What do you think of that?? Do you have a good design?? My neighbor was brainstorming with me and thought about using a shackle and a bar. I don't think that this is good. What do you think???

Another thing is that I'll take my spring packs out again and loosen the clamps. When I added the leaf, I didn't open the clamps. I just hit the extra leaf between the others, so the leaves are VERY tight in the spring clamps. I can hear them squeezing. When I loose the clamps, I'll also remove the second longest leaf that I added, and replace that with an extra longest leaf (after cutting the eyes off). WHAT KIND OF TORCH IS THE BEST TO USE FOR OPENING THE CLAMPS??? After adding the leaf, I'll put a block in to get a half inch distance between the top leaf and the clamps. Of course, I'll remove that block after re-shaping the clamps (thanks Lars). I'm also thinking of putting the smallest leaf back in that I removed for the length of the center pin. I'll buy longer center pins.

And one of the most important lessons that I learnt this weekend is that ARB lockers are also very handy in the Netherlands. I had to winch myself out two times. The first time, just because I couldn't make it with open diffs (maybe I could with the anti-swaybar disconnected, but I was too lazy), the second time because I was so stubborn. That was the same spot. I turned and just wanted to try it again. One of my next upgrades is ARB's front and rear. I'm just not sure if it's a waste of money to put them in a D30 and D35. Maybe I want stronger axles later..... BTW my setup is a '88 YJ 258 with 33" tires and auto transmission. I have 4,10 gears in my hands, but still have to let them install (together with the ARB's???).

Want to keep it short, so that's it for now. Pictures will follow later on my website.

Gilbert Verkuijlen.

Internet: surf.to/jeepmania

or: www.geocities.com/Baja/Dunes/5323/gilbert.html

Email: Gilbert@airforce.net

I just opened up my spring clamps last week.

See http://www.jedi.com/obiwan/jeep/addaleaf.html for details. Photos are still in the camera, unfortunately.

Propane will work, but it will take a while. I switched to mapp-gas (methylacetylene), and it went much faster. Oxygen is somewhere in between.

My question is "why bother bending them back?" When I maxed out my articulation before adding a leaf to my '95, I found that the clamps never touched the top of the axle, even under max droop, which means there's no obvious reason to have them bent back over the top again. Who knows, you may want to add another leaf someday, which means you'll have to bend them out again. I say save yourself the trouble and

leave them pointing straight up.

-- Obi-Wan

'95.5 YJ, RE add-a-leaf

--

Ben "Obi-Wan" Hollingsworth bvh@inetnebr.com

Vice President and System Administrator, Internet Nebraska 402-434-8680

That's what owning a Jeep is really about. Being the sort of person

who sees people in need...and scares the crap out of them. -- Zen

[snip]

Oxygen-acetylene is the fastest (hottest) but if you want so save some money, propane-oxygen is cheaper and almost as hot. These are two-tank torch setups. The single tank things like the butane- or propane-only are not going to be hot enough.

...lars

I added a leaf to my spring packs, and I simply bent the clamps open, and left the ends pointing straight up. Then I drilled a hole in each end, and inserted a bolt and tube spacer through the hole. This setup has worked fine for me on several different Jeeps. I used an Oxygen-Acetelyene torch to heat the clamps cherry red, and they opened very easily.

I've been seriously considering fabricating a "ladder bar" for my CJ. I'm thinking of making it out of .188 wall 1 1/4" round tubing, with heim joints on the ends, and a slip yoke from a drive shaft to allow axle articulation. I'm going to centrally mount it, near the pinion, and connect to a custom crossmember right behind the transfer case. This is still in the design stage, but that is my general idea. Any other suggestions?

Best Regards,

Chris Kutish

Chris - two things:

- If you put pivots at both ends plus a slip yoke, the bar will have no effect at all - it will simply follow the axle as it rotates under torque. To make this work you have to fix one end of the bar - preferably the end attached to the axle. This way when torque is applied to the axle tube, the bar tries to rotate upwards with it and is prevented from doing so by the connection to the crossmember. Fix the axle end by welding or bolting the bar to the tube in at least two places, bracing it as much as possible for strength.

- a driveshaft slip yoke is splined so that there is no freedom for one end to twist relative to the other, but for an anti-wrap bar you want this degree of freedom so that the axle can articulate (one wheel drooping, the other compressed) while the body stays level. So instead of a driveshaft slip yoke I think you want to fab up something similar, except with a smooth bore instead of splines.

Like you I've been toying with this idea for awhile. Gotta put something in there before my OME springs start to sag from the axle wrap in my SOA setup. The telescoping rod thing is a good system, but I can't think of a way to make the telecoping part without the services of an expensive machine shop. The tried-and-true ladder-bar with a shackle on the crossmember end will work just as well, but while you don't need the telescoping section you do need extra room for the shackle to move in.

You're right about keeping it close to the driveshaft - the pumpkin moves the least of any part on an articulating solid axle, so that's where you want this kind of control arm.

Chris (brain hurts when thinking about this geometry for too long)

Uh... maybe I'm missing something here, but if you put a slip yoke on it, how's it gonna prevent axle wrap?

-- Obi-Wan

I'm not a mechanical engineer, but...

If you attach a pivot at the same end as the fixed end of the spring pack and attach a pivot above the axle making the bar the same length as the front of the spring pack and parallel to it, wouldn't this solve the wrap problem. Since the spring can't get longer and shorter you wouldn't need the slip yoke. Also you should be able to keep full articulation.

Just a thought,

Randy

I did the ladder bar with a shackle, but I added a threaded portion near the front end to allow twist. It works great. I used polyurethane bushings at all three corners plus the top of the shackle, with the threaded part there is no need for a heim joint.

I made mine from old steering draglinks from a Wagoneer and Scout II, leftover CJ shackle end spring bushings and some 1" tube to hold the bushings. Yeah, I'm cheap but the stuff was handy. I managed to bend the solid 1" main bar (from the Wagoneer) while testing out my lincoln locker by reving my 258 to 3000 rpm in dropping the clutch in 1st gear low range on dry pavement with aired down Swampers. I straightened it in my press and it's been fine since. It never sees that kind of abuse in real life, only in testing so I'm not real worried about it.

If I had to do it again I'd use .188" wall seamless tubing and I'd change the design slightly to make the apex of the triangle closer to the front of the bar to prevent future bending.

Don't forget to place the bottom bar about 1" lower than the driveshaft and running paralell to it to protect it in log crossings.

--

John Nutter '85 CJ7

Http://www.off-road.com/~jnutter

Hey, ya know.... there are some clamp-on spring clamps that might work for a solid connecting point at the axle. Check out the following link:

http://www.loufegersracing.com/

and look around for the clamp-on spring clamps. They're only $25. Just a thought...

- Doug

Mike Garner's done this with bars like those adjustable TJ control arms, and apparently had a lot of luck with them.

Thing is, though, that while the spring doesn't get linger and shorter, it DOES change shape as the wheel droops and compresses, so the distance between the spring plate and the frame mount does increase and decrease. So a bar in that location would ideally need to change length...

I've decided against this approach for that reason. On paper it looks like it limits articulation too much - or at the very least it fights the natural motion of the springs. Hard to argue with Mike's experience though.

Chris

Sorry if I wasn't clear, but I plan on fixing it to the axle on top and bottom, like a trianglle, and to the crossmember at the other end. Total of three points of contact.

Will this work?

Chris

That's a ladder bar! :-)

It should work to completely stop wheel hop, but a shackle on the forward end would help articulation a lot.

--

John Nutter '85 CJ7

Http://www.off-road.com/~jnutter

Was that the yellow jeep with the bar that used a splined driveline shaft? That's one of two designs that I like. The other is the shackle. None of the commercial systems that I've seen use what I think is fundamentally required: a variable length bar. This is needed to account for the change in length as the front half of the spring flexes. Otherwise something will bind up. The more articulation the more of an issue this will be. There is also the issue of the rotation that the bar needs to allow through the full articulation range. The splined shaft had a setup similar to the bushing on a Bronco front end. You could also use a shackle and heim joint. Both systems only require one solid bar. Set up the shackle so the bar end of the shackle is above the frame end. I also think the splined shaft setup has the potential to be designed so that the bar is made from a spare driveshaft.

When I get that far into my project I'll be using one of these two methods (I tend to favor the one that gives me a spare drive shaft though I'll have to look a bit more into strength issues).

Jeff

Gilbert,

I would use a rod with heim joints on either end and weld a mount onto the top of the differential, and link the other end to a crossmember that is the same distance from the axle as the spring hanger -- I know, easier said than done, but that would probably work the best. Course, I'm not a suspension designer.

Roland

Ive seen a double tube setup...esentially a pair of tubes, one pair on each side, about 1.5" o.d. on the outside tube, and another with the same o.d. that matches the 1.5's i.d. The larger tube has a bracket which mounts at the forward spring mount, and the smaller tube which fits inside the larger mounts to the spring plate near the u-bolts. The round design allows the axle to articulate without binding ( use a zerk (grease) fitting on the larger o.d. tube so you can grease it so it moves better ) and slip in and out for change in length, but will not allow for torsional rotation of the axle due to the tubes close tolerence inside each other.

Thanks to all for their detailed reply. Does anyone have any pictures of an anti-wrap bar???

Thanks. Will use methylacetylene or oxygen-acetelyene.

[snip]

[snip]

Thanks. This is what I'm going to do. I just installed an OME lift for a German Jeeper and they also have this design. I like it and don't see the disadvantages.

[snip]

[snip]

This is exactly what I saw in Petersen's of November '97, only I'm not sure about the heim joints. How do you want to mount it in the center (I have an YJ)??? How far can you mount it from the center without having problems??

[snip]

OK, but then I don't understand the design what was in Petersen's. That guy (his name is "Wrongway") used a driveshaft slip yoke.

> I did the ladder bar with a shackle, but I added a threaded portion near the front end to allow twist. It works great. I used polyurethane bushings at all three corners plus the top of the shackle, with the threaded part there is no need for a heim joint.[snip]

I'm very curious. Is it possible to see the design of the threaded portion?? Do you have any pics?? Does the threaded portion cosists of "rings", or just like a regular bolt and nut??? Do you understand what I mean?? Hard to explain for me in English.

[snip]

Yeah, I know. I gave this advice to other Jeepers. This will also work fine for the anti-wrap bar. Thanks for the info.

I'll cc him in this mail and see what he replies.

So the design is very easy?? Just a ladder bar, threaded portion, shackle, fix it on a few points and whatever I forgot????

Gilbert Verkuijlen.

Gilbert@airforce.net

Ok, I'm caught up now. Geez, you guys took off like a shot on this one. ;-)

I've seen springs made this way. I like the design, myself. I'd do it, IF I had those kinds of clamps.

I would 'think' that it could be mounted anywhere on the axle and still work. Theoretically. In practice, putting it right next to the cast housing (either side, whatever works best) would be plenty close to the center. It will just have to droop a little more when that side is drooping.

[snip]

I 'believe' that Wrongway used a mounting at the front, very much like the upper mount on a stock YJ front shock. Only larger. This would allow for any twist, the rubber bushings allowed the droop, plus it provides some isolation from the driveline noise. Every article I've read on the web where someone used a solid connection, like a heim, had something to the effect of: "In the future I will redesign it to use some sort of rubber or poly mount to lessen the road noise transmitted to the body."

[snip]

Mine was a BIG bolt, about 1.25" in diameter. I suspect John did the same.

I've cut and pasted Chris' whole note below, so I can address some things.

Haven't see this, but I like the sounds of it.

I used a poly bushing on each end to isolate road noise, and.......

allow for the change in length. When I first built them, I thought, "These are going to rob all kinds of articulation, but I have such a problem, I will just make these up, and see if it works. If it does, then I will do something more permanent." (at that stage, I wasn't convinced I was keeping the SOA) As I built them, I compressed the spring till it was flat. I then measured between my two mounts. At full droop I measured again. Difference in length, 1/2". I know the poly can account for that. The rear mount is on top of the spring plate, so I definitely loose those 2" of compression. It will be perfect, when I go to 35's, with 33's, I'm giving have a little space left at full compression.

It does limit articulation, It does fight the natural motion of the spring. In my case, neither was severe enough to cause problems. YMMV

Hope I'm caught back up now.

mike garner (glad we don't all do things the same way. What would we have to talk about?)

'72-'89 Feeplikething

Should work fine with two mounting points on the axle and a third on the crossmember, aslong as you've got that slip yoke in there. Use a heim joint for the crossmember connection if you want (I'll probably just use a poly bushing in an old shock eye and a bolt), but don't bother with them on the axle side. You don't need joints there since there's no motion at those points, so just weld or bolt the bar on and save some $$.

Lars gave me some good advice a while back regarding the axle-side connections. Knowing very little about welding, I assumed it would be possible to weld connecting tabs directly to the cast diff housing, but apparently that's a PITA. He said to plan for welding those tabs to the tube instead. One on top and the other on the front of the tube, I reckon, so the bar has a triangular frame. And keep 'em right close to the diff to minimize the effects of articulation.

Anyone got any ideas on where to find or how to make a nice strong non-splined slip yoke for this thing? Something like a shock absorber would be ideal, but probably nowhere near strong enough...

Chris

The main bar is simply threaded and screws into a sleeve that has the front bushing in it. It's just the threaded part from the Wagoneer draglink with the adjusting sleeve. Just the parts you would use to adjust toe-in on a front end but used differently.

If I was making it from tubing I would used some grade 8 threaded rod fit into the back half and a nut welded onto the front half to allow it to rotate. I'd use the biggest threaded rod that would fit into the tubing and I'd weld it securley.

This also lets me fine tune the length of the ladder bar for best opperation.

--

John Nutter '85 CJ7

Http://www.off-road.com/~jnutter

Missed seeing this when I sent the first message.

That's all it is. It stops wheel hop and allows every other movement.

All you need to do to stop wheel hop is to control pinion angle. Hop can't happen if the pinion can't go up and down under acceleration and braking. That's all mine does, every other possible movement is allowed to happen. It doesn't seem to restrict articulation at all.

--

John Nutter '85 CJ7

Http://www.off-road.com/~jnutter

[snip]

OTOH, you've got a 9" rear end so it doesn't use a cast diff. It would be easy to weld to YOUR diff housing.

If you can find the right piece of metal for the outside sleeve (non-seamed), we should be able to turn the inside piece on the lathe so that it fits very snugly. The main problem is keeping the grease in it. What kind of seal can we use?

...lars

Motorcycle fork seal? I'd almost say just adapt one fork tube, but those aren't designed for the stresses you'll encounter. Speaking of which, with the tube within a tube design, any bends at all in either tube will restrict the amount of slippage that can happen, or just bind the two together.

bs

It'd seem to me that if you're gonna turn it on a lathe, could you not put an o-ring groove inside the edge of the big tube, and another groove on the outside of the smaller tube? Naw, you wouldn't want both ends sealed - then you'd lock up with air and grease pressure. Okay, mebbe just on the inside edge of the larger tube? And fit a zerk into the outside tube... But if you're planning on fitting it so close, why do you need a seal? Just stick some grease in there with the fitted zerk, and it should be good to go. It's not like you're gonna be pulling that shaft a foot in and out whenever you hit a bump. Say, mebbe a boot to cover the operating range of the smaller tube. That'd look pretty neat!

- Doug (just thinking outloud, don't mind me....)

'94 YJ

Sounds good to me. A boot with a drainage hole would be a good idea, but even then, many driveshafts don't use a boot over the slip joint, or a seal for that matter.

True, but I think this could be overcome by having lots of overlap, like at least 12". There's a good bit of distance between the axle and skidplate (which I'm thinking of mounting the top of the bar to). The amount of travel for the bar should be no more than in the slip yoke of the rear driveshaft (3-4"), so there's lots of room for the tubes to overlap in.

Chris

I don't know if they still sell it but Chrysler performance use to have a thing called a pinion snubber. It bolted to the pumpkin if I recall and had a rubber bumper that was pointed up towards the floor pan. As the axle tried to rotate the snubber hit the floor pan and stopped the hopping. Not sure how well it would work on a Jeep, but it wouldn't limit articulation. However, as I think about it our suspensions are probably too far away from the body for it to work. Doh!

David

--

The Moulton Family!

[snipped his family]

:) :* :( :P mailto:moulton@ns.sympatico.ca

See our family page @ http://www3.ns.sympatico.ca/moulton

See our Jeep page @ http://www.off-road.com/~moulton

sorry, didn't get to read much of yer post (pressed for time) but have ya considered using good, stiff shocks - aka "kicker shocks" ?

that way ya wouldn't have any fidgeting with length so as to not limit wheel travel - also, try setting up the rear shocks like the XJ - ie, one infront of the axle & the other behind

hope this helps

carlos

Well, it is possible, but I got a lot of good suggestions of making an anti-wrap bar, and it doesn't look that difficult to design and make one. Looks like the ladder bar is going to be my design. If you're interested I can send some replies that I got.

Hmmm, never thought about that. Even didn't know that XJ had that setup. Is that only with the SOA XJ's??? Never looked under a XJ. XJ-drivers are another type of people in the Netherlands. However, this might work, although the anti-wrap bar still looks the best solution to me.

Gilbert Verkuijlen.

ya - send me some of the suggestions for anti-wrap bars or betterr yet post it on yer site & i'll check it out

as for XJ's, they're all SOA - the shocks r mounted the way i described cos sometime ago GM engineers found that configuration to greatly limit axle wrap

OK, I'll put all the replies that I got on the internet. I'm just looking for some pics of an anti-wrap bar. Please send me your design, drawing, pics or whatever. Then I'll make same conclusions and the way I'm going to do it. I'M LOOKING FOR PICTURES!!!!!!

Will tell you when the info is on internet.

Gilbert Verkuijlen.

Gilbert,

Just thought I'd clarify my suggestion with a drawing. I didn't quite understand what some of the other people were suggesting, so I thought I would clarify mine just in case.

Groetjes,

Roland

Yes, EXACTLY. His name was something like "Wrongway". The vehicle was a yellow flatfender.

Let me know when you start earlier on this project.

Not sure about the heim joints, but will take the same distance as from the axle as the spring hanger.

[snip]

OK, have to study about this, but what's the difference with a shock (very stupid question)???

I got a lot of good suggestions of making an anti-wrap bar, and it doesn't look that difficult to design and make one. Looks like the ladder bar is going to be my design. If you're interested I can send some replies that I got.

Gilbert Verkuijlen.

No such thing as a stupid question...unless it regards Scouts. (Just Kidding). A shock has bushings at either end. bushings flex and let the axle begin to wrap. The rear of the setup would have to be solid-welded to the bracket that mounts to the spring plate at the u-bolts, no flex there. Then the other end, with the larger o.d. tube that mounts near the forward spring hanger, is a solid up/down swing joint, be it a u-joint, sleeve and hard bushing, flanges with a nylon washer between contact points so it can pivot, heims, etc...(the side rotation for axle articulation is provided in the rotation of one tube inside the other.). Also picture the tubes... say both 1.5' long, and the one inside the other about a foot. The contact area of the i.d. vs. o.d. would not allow the assembly to "bend" or allow torsional rotation of the axle tube due to the surface area. A shock is not designed to be loaded with torque sideways, or bent into a "V" if you will, thus the bushings, thus the wrap inherent in the design. It may slow it, but not control it completely. the contact area is also only at 2 points on the shock, at the seal(not good) and at the piston in the shock body. the rest of the area inbetween these two is simply open space with hydraulic fluid, whereas the twin tube design has contact ( read that reinforcement or bracing) along tha entire length of contact, or more simply put, is distributing the load of the torsional rotation along a larger and stronger surface area. Gee, that was a lot of typing. Hope that helped... if not, e-mail me and a relatively simple drawing can be sent explaining the whole thing by picture. It seems to work very well, and is relatively cheap and easy to build.

Terry Baker .02c

As mentioned it allows rotation at the axle mount, thus it is not a true anti-wrap setup.

Ladder bars and leaf springs don't mix very well since one changes length and the other doesn't. Street rods will get away with it because of their limited suspension travel. I've seen a setup that lets the leafs float in the axle mount (Jegs or Summit) that is designed to get around this. Traditional ladder bars also take a lot out of your ground clearance. They look cool though.

Jeff

Of course, this is a very important subject. And now you guys, can finally impress a European Jeeper with your knowledge.

Is it not possible with the original clamps?? Too short?? I'll try to find other clamps if necessary.

[snip]

OK, see further what I'll use.

And this is what I'll do (or the shackle). Because he used a splined slip yoke, do you think that the rubber can twist enough (so you can use a splined yoke)?? Have to look closer at his design.

OK, thanks.

OK, and now a stupid question.... How does a ladder bar look like?? Never seen it.

[snip]

[snip]

Oh, is that all??? I expected more. Have to measure that with my setup.

I also came with that suggestion on JeepTech and this was their answer:

A shock is not designed to be loaded with torque sideways, or bent into a "V" if you will, thus the bushings, thus the wrap inherent in the design. It may slow it, but not control it completely. the contact area is also only at 2 points on the shock, at the seal(not good) and at the piston in the shock body. the rest of the area inbetween these two is simply open space with hydraulic fluid, whereas the twin tube design has contact ( read that reinforcement or bracing) along tha entire length of contact, or more simply put, is distributing the load of the torsional rotation along a larger and stronger surface area.

Sounds good.

OK, if everybody can send me their design, drawing, pics or whatever concerning the anti-wrap bar, I'll put it on the internet together with all the replies that I got. Then I'll make same conclusions and the way I'm going to do it. I'M LOOKING FOR PICTURES!!!!!!

Will tell you when the info is on internet.

Gilbert Verkuijlen.

> A shock has bushings at either end. bushings flex and let the axle begin to wrap. The rear of the setup would have to be solid-welded to the bracket that mounts to the spring plate at the u-bolts, no flex there.

[snip]

Ho, wait. I mean the principles of a shock. I don't mean the mounting of a shock. You were talking about two tubes or whatever. I think that the principle of a shock is the same.

[snip]

[snip]

OK, this is a very good reason. BTW I'm not considering the shock principle. Just wanted to discuss it.

[snip]

Yes, please send me the drawing. If everybody can send me their design, drawing, pics or whatever concerning the anti-wrap bar, I'll put it on the internet together with all the replies that I got. Then I'll make some conclusions and tell you the way I'm going to do it. I'M LOOKING FOR PICTURES!!!!!!

I got a lot of replies about the ladder bars and how good they work with their setups. All I know till now is that they use a ladder bar, shackle, a threaded portion, fix it on a few points etc.

Gilbert Verkuijlen.

It's a PITA. You'd pretty much have to make a whole new crossmember to hold the top ends of the shocks. The stock configuration has them on such an angle that you can't really mount one to the other side of the tube...

It would help control axle wrap if you could find a way to do it, though.

Chris

I've always been curious as to why exactly this setup helped axle wrap. Why is having one shock coming off the back of the axle better than having both come off the front (like a YJ)?

Another question: when I make my custom lower shock mounts for the XJ D44 on my YJ, would it be bad to move the lower mounts inboard on the axle 8" while keeping the stock upper mounts? Would that increase body roll? I wonder, because I seem to recall Craig saying that moving the upper mounts inboard decreased body roll on his SOA YJ. I'm trying to increase shock length without decreasing ground clearance or re-routing my exhaust.

-- Obi-Wan

'95.5 YJ

Now there's a new idea (to me anyways). You lose ground clearance is the obvious answer. You may need to add a panhard bar (which now basically gives you a three link) if the front shackle causes to much side to side slop (remember the handling issue front shackles are giving people). It doesn't seem that much harder then to go coil (which I think would be the final solution). I start to get very nervous, though, about taking suspension mods this far for a street driver mostly because of the current politics of lifted and modified rigs and the vacuum of intelligent critical thought within the court room. Any minor fender bender could become quite ugly when someone notices all that funky homebrewed suspension mods. Then there's the issue of the ever more popular safety inspections. This doesn't mean that the idea isn't a good one.

I don't see anything easier, cheaper, or more effective that the solid single bar attached to the pumpkin with a front shackle and heim joint.

I'm also of the opinion that axle wrap is not going to be much of a problem unless you plan on some vigorous wheelin' with a big motor and a heavy foot or very soft springs (which you shouldn't need with an SOA).

Jeff

I'm gunna ask the dumbest non Scout question I have ever asked. :)

What is a heim joint?

Sounds like something someone once offered me at a concert...

Zen (gunna go score some quality heim)

There also called Rod Ends (Heim was the German who invented them)

check out http://www.artmorrison.com/tech_rod.htm

Jeff

A few tips on the Anti-wrap (traction) bar:

The single link upper bar acts in conjunction with the lower leaf spring attachments to make a poor mans flexible three link suspension system.

The axle end should be solid to keep the pinion angle controlled. You have one chance to get it right, if you weld it directly, so be carefull. A bracket is better.

Weld a bracket to the right side steel tube or make a heavy steel bracket that bolts at the diff cover bolt holes and wraps around the right side of the axle.

You want the bar on the right side of the diff to counter driveline rotation torque.

You want the bar mount away the axle centerline and spring pads, if possible, to spread the load torque (achieve a better lever arm) between the two leafs and the bar.

Using a shackle and rod-end at the bar's leading end is the cheapest method to allow both forward/backward and rotational float.

Make it the same length as the driveline with the shackle arc in line with the front u-joint. The goal of the anti-wrap bar is to protect the u-joints by keeping the pinion angle (nearly) constant. Parallel the u-joints to minimize force on the joints.

At this point (neglecting max weight transfer concerns) the angle of the bar in relation to the springs and ground is not extremely important. Designing the front shackle to bar mount lower than the axle centerline (tilting the bar lower in front) will (instantly) stretch the front half of the leaf spring packs under load. This is better, if possible, because springs are more controllable (react better) in tension. This also moves the leverage point where the bar feels the vehicle weight (instant center) forward and longer, resulting in more wheel force & traction (maximizing weight transfer.) This will allow a more flexible forward half of the leaf spring pack for better articulation (stiffening the forward half of the spring pack, using a slapper type traction bar, will help traction but reduce articulation.)

The anti-wrap bar, can be a ladder or single tube of sufficient strength. Making a bracket at the axle end that allows pinion angle adjustment will duplicate the better ladder bar designs. You will need this if you change lift height. Changing shackle length allows some pinion adjustment but it is limited. Look at bar adds in National Dragster magazine or any drag race competition publication (web search should find pictures.)

Fully floating the axle (shackles at both ends of the leafs) will allow the bar to be hinged at both ends -- but you will now need more bars (a four link system) to keep the axle from crabbing. At this point you have so much stuff attached to the axle that 1/4 eleptic springs and a custom three link system look attractive.

I usually stay on the XJ-list but this is a topic covered extensively on the general off-road-list a few years ago. I also spent many long weekends making leaf sprung vehicles run 10 second quarter mile times. There is alot to consider.

Happy Trails!

Ed A. Stevens

stvns@aol.com

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