Rear Spring Wrap:

So I'm just a few weeks away from installing my Clayton 6.5" Hardarm kit on my XJ, and it occurred to me that many other rear SOA applications have issues with axlewrap. I'm assuming that the engineers who design these kits take that into account, but I have no experience on this as it relates to XJs. I have a SOA CJ that had major axlewrap issues before I fabbed a traction bar, it was particularly bad on steep rock climbs.

Who has had axlewrap issues on their XJ? Do any particular kits seem more/less prone to this? I know there are kits such as Sam's Off Road that can be used to combat this, is it going to be an issue on my XJ?

It's not a huge issue until your springs get old and saggy .. at which point you probably need to replace or rebuild them anyways.

Good to hear. But it is an issue on some level? Do you know of anyone running a rear anti-wrap bar?

It can be an issue, but isn't always. Depends how soft your leafs are and how hard you are on the throttle. I've heard of a few people running anti-wrap bars, but they are a loss of clearance, so I dont think many people do. I had a lot of wrap on my last set of leafs, I threw an extra leaf in each to stiffen them up (off of an F150 rear end) and then later replaced them with new leafs.

HP + wide tires on rocks + fat foot = axle wrap (somtimes)
Your driving habits have a lot to do with it. It's been gone over mant times.
If you find your are having this problem DO fix it fast. This is the stuff that trashes springs and drive train fast.

This is something I've been dealing with on my XJ ever since I went to 35's a few years ago. I'm part-way through fabbing a traction bar, but just got some new springs which are supposed to resist wrap more than my current ones, so hopefully they'll help and I won't have to worry about the traction bar anymore.

The other thing that can help is ant-wrap spring perches. They are basically just longer perches. I run the Rubicon Express ones, with 35's, 4.88's and a detroit on RE leaf springs, and get next to no wrap at all with a heavy foot.

I'm building my first XJ and have no idea if they are any better or worse for axel wrap. What I do know is that axel wrap couses loss of traction, major breakage and have seen rollovers due to it. I would not ever want to do anything but crawl without a real Anti wrap bar. Forget the so called antiwrap spring perches and antiwrap springs.They don't control the kind of wrap induced by hard off roading. I have not built my bar yet but won't be in the woods without one. One cheap and easy way I am thinking of is I will take a long spring perch and weld it horizontal on the axel then use tractor top links (cheap) and run foward to a shackle mounted to the skid plate. Copy of the sam's off road unit. In addition I allready use long dana 60 perches on my 8.8 end have an extra bottom leave on the pacs.I may even just buy one from Sam's off road If I like the lenghth because that design is proven OK. I saw one wrap so bad on a CJ it broke the moter and transmission mounts and shoved the engine thru the radiator. I watched another guy wrap so bad he broke his JB conversion SLE and wound up rolling. He was warned to lock the breaks if he lost momentum but he kept in it and on about the 3rd bounce he broke and ruined his clean ride. I know most of y'all don't need the safty lesson but if you start to bounce on a hill climb that is axel wrap. Back off on the first bounce.

Stumpalump said:

Forget the so called antiwrap spring perches and antiwrap springs.They don't control the kind of wrap induced by hard off roading.

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Yeah, what to do those of us that run them know?

I had axlewrap issues when I bought my XJ. Previous owner had 2" blocks, stock springs, with an add-a-leafs, and 2" shackles. Do not go with blocks. After blowing up 3 yolks, I replaced the rear springs with a set from Iron Rock Offroad. No more problems.

Everyone has axlewrap to some extent, there is no avoiding it, it is much more severe in sprung over vehicles and I am not engineer enough to tell you why but it is real.

Axle Wrap is primarily caused by gaining and losing traction rapidly, as in climbing a steep slope with parts good traction and parts bad. as the wheels spin and then suddenly gain traction the vehicle hops.....It also occurs when changing quickly from forward to reverse or vice versa for the same reasons.

We combat Axle Wrap a couple of ways already mentioned here, 7" long perches and an anti wrap bar, our anti wrap bar is designed to "Lay Back" like a chaise lounge to lose less clearance. Height is not neccessary, only the holding the axle center at a given point. We have actually talked of making a bar that looks like a spanner wrench but the cost would be too high.





I've shown the Anti Wrap kit with the side plate stiffeners (they come with bushings, 5/8" bolts, & sleeves) and a pair of the perches......

Overall, Wrap isn't really avoidable but it is controllable if it affects you too much.

Dan Fredrickson
www.ruffstuffspecialties.com
916.600.1945

cal said:

Yeah, what to do those of us that run them know?

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If you read my post I said I run them also, They are the same as a long Dana 60 pearch. I also use an extra spring for anti wrap. This is what you need to control small amounts of wrap like on the street. Climb a hill and hammer the throttle with lockers and real tires and they won't stop wrap. Only a stought antiwrap bar can handle that load. Have your buddy drive you jeep and you watch the pinion move on take off. Now imajine climbing a hill with all the weigt on the back and the jeep bucking. Thats when you will see the wrap that can kill you. The rear yoke or whatever breaks while your foot it in the gas. All of a sudden you are up on a hill and get lounched backwards. So you nail the breaks but thanks to the proportioning valve you now only have 30-40% on the breaks witch is now actuall the foward direction of the jeep. The front locks up and slides the rear does nothing and you are forced to slide backwards down a hill. (see most common reason for a roll over).

Gravel Maker said:

Everyone has axlewrap to some extent, there is no avoiding it, it is much more severe in sprung over vehicles and I am not engineer enough to tell you why but it is real.

Axle Wrap is primarily caused by gaining and losing traction rapidly, as in climbing a steep slope with parts good traction and parts bad. as the wheels spin and then suddenly gain traction the vehicle hops.....It also occurs when changing quickly from forward to reverse or vice versa for the same reasons.

We combat Axle Wrap a couple of ways already mentioned here, 7" long perches and an anti wrap bar, our anti wrap bar is designed to "Lay Back" like a chaise lounge to lose less clearance. Height is not neccessary, only the holding the axle center at a given point. We have actually talked of making a bar that looks like a spanner wrench but the cost would be too high.

I've shown the Anti Wrap kit with the side plate stiffeners (they come with bushings, 5/8" bolts, & sleeves) and a pair of the perches......

Overall, Wrap isn't really avoidable but it is controllable if it affects you too much.

Dan Fredrickson
www.ruffstuffspecialties.com
916.600.1945

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Thats the pearch I bought and they sell the biggest u-bolt and plate set-up I have ever used. Nice folks but I did't follow him on why his anti wrap mount was better. Maybe you can explain it. Buy the looks of the 8.8 install kit I got from them I'm sure it's overkill(the good stuff).

I put a anti-wrap bar on my XJ right after I locked the back. I noticed during climbs and even just driving down gravel roads the rear end wanted to bounce and loose traction. This was with brand new leafs.

After the wrap bar I can stomp the go peddle and the rear tires just plant hard and the whole rig takes off. It made a huge difference, so much that I don't run without it one anymore.

Stumpalump said:

If you read my post I said I run them also, They are the same as a long Dana 60 pearch. I also use an extra spring for anti wrap. This is what you need to control small amounts of wrap like on the street. Climb a hill and hammer the throttle with lockers and real tires and they won't stop wrap. Only a stought antiwrap bar can handle that load. Have your buddy drive you jeep and you watch the pinion move on take off. Now imajine climbing a hill with all the weigt on the back and the jeep bucking. Thats when you will see the wrap that can kill you. The rear yoke or whatever breaks while your foot it in the gas. All of a sudden you are up on a hill and get lounched backwards. So you nail the breaks but thanks to the proportioning valve you now only have 30-40% on the breaks witch is now actuall the foward direction of the jeep. The front locks up and slides the rear does nothing and you are forced to slide backwards down a hill. (see most common reason for a roll over).

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Hrm. In my 15 years wheeling, I have never broken a yoke or rolled a rig because of axle wrap. Maybe I know how to drive, or maybe I run better springs than you do.

And if your brakes work right, you won't have a problem backing down a hill.

I broke a u-bolt on my pinion yoke once, due to spring wrap trying to climb a ledge, but that's it. I do have some neat vids of my axle wrap on take-off on level ground though.

If my Jeep starts hopping whilst I'm climbing something, I get off the gas. I also see linked suspensions (TJs) hop just as much as leaf-sprung rigs (XJs)...

The axle wrap I've got, I've never 'felt', in fact I would never have known I even had it unless someone hadn't said something while they were watching me climb a ledge.

what about grabbing an MJ overload spring. It's about the largest "anti wrap" leaf you'll find.
I left them on my MJ, they're about 1/2" thick and extend half of the main leaf.

Thanks for the replies. Yep, I'm unfortunately familiar with axle-wrap, tossed a rear driveshaft on my CJ years ago, limped home in front wheel drive, and fabbed a traction bar before wheeling it again. My question was, is it an issue on XJs in particular, and it sounds like some set-ups are more prone to it than others. I'm getting the RK 6.5" springs, I have no idea if they're thick or stiff enough to combat this. I'm trying to avoid a bunch of fab on this ride, I got all of that out of my system on my CJ. So is the Sam's Off Road bar still considered the best choice, or is there another one that works better on XJs?

Stumpalump said:

Forget the so called antiwrap spring perches and antiwrap springs.They don't control the kind of wrap induced by hard off roading.

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That comment is not entirely true. It depends on the application.
Leaf spring design (as well as longer perches) can GREATLY affect spring wrap.

I remember being able to send my rear yoke into bind with the stock leafs on our XJ years ago. (just on dry pavement) Simply swapping in a set of OME leafs cured that. That was running 31's though.

Of course, the bigger the tires you run, the more weight on the rig, the amount of throttle applied and the bigger the obstacles all play a part in how much spring wrap you'll get with a given leaf pack.

We run 35's, locked up and play in big rocks with our XJ's. Our new TrailGunner leafs (7-leaf pack with anti-wrap clips) are PLENTY substantial for wheeling this set-up with no traction bar. Sure, there's a BIT of wrap on bigger obstacles, but nothing that causes yoke bind, hopping or loss of traction.

Now if youre running an extremely heavy rig on one tons and 40" tires, you've basically left the norm of what you'd consider most (dual-purpose) XJ's to be. At that point, you are easily into lots of custom fab, uni-body re-inforcement, etc and a traction bar would most likely be mandatory.

One of my guys is running a traction bar on his XJ with 37's, but he flipped the rear springs. Because of the center pin location, that's instant spring wrap.
As Jason can attest, it's not real easy fabbing a traditional traction bar on an XJ. The one Alex did works fantastic, but involved cutting out a good sized section of the floor and fabbing a crossmember/mount to do it.
That rig doesn't see street duty though.

For the vast majority of guys that are running 33-35" tires, there are springs that are perfectly fine without a traction bar.

I have had issues with axle wrap and recently added some S-10 leaves to my extremely sagged pack (due to axle wrap) and am in the process of building my own traction bar to stop it from destroying the s-10 leaves I've added in. Most of my problems come from driving and climbing hills in loose dirt and sand.

Axle wrap may not be as noticable on an XJ (SOA) as long as you don't have lift blocks, but its still there. The blocks just increase the possibility by increasing the distance between the center of the axle and the spring which acts like a lever arm allowing the torque from the engine being transmitted to the ground to have more of an advantage on the springs resistance wrapping causing them to weaken and wrap up more over time.