Rear Axle Wrap Prevention in Jeep Cherokee XJ

By Dino Savva

All Jeep Cherokees built from 1984 to 2001 are equipped with leaf spring rear suspension with the springs over the axle (SOA). This makes them particularly prone to axle wrap because the rear axle is only located by the springs and the rear driveshaft assembly. Axle wrap is even worse when a suspension lift is added or if you increase engine torque output with performance modifications.
Axle wrap occurs when the rotational force of the tires causes the axlehousing to twist or rotate. This rotation forces the springs to bend into an S-shape. When the axlehousing rotates far enough, forces cause the tires to lose traction and jump, or "hop". Once traction is lost, the springs snap back into their original positions. This happens over and over until the truck gains better traction or the driver reduces torque input by letting off the throttle.
If axle wrap is allowed to continue unchecked, wear & tear on various components (internal axle assemblies, tires, shocks, shackles, U-joints, and leaf springs) is accelerated and the risk of breakage increases.
There are many ways to prevent axle wrap and John Nutter's excellent article describes a few techniques.
Axle wrap became even worse in my '92 XJ after I swapped in a 4.6L stroker engine. It became almost impossible to launch the vehicle quickly from a dead stop in 1st gear without inducing severe wheel hop. I decided that the only way to prevent this was to add a traction bar. Unfortunately there aren't any off-the-shelf traction bars available specifically for the XJ so I had to take the custom route.
I considered all the options that John Nutter described in his article and chose the single bar below the spring set up to keep things simple. I found a traction bar that had the attributes I was looking for cheaply on e-bay. It has 3/4" left and right threaded heim joints at both ends so it can be adjusted to any length from 20-28", and is a heavy duty tractor part so it should be super strong.

Parts List

Custom traction bar
Two custom-made heavy steel mounting brackets
Two 3" long 3/4" diameter grade 8 steel bolts with 27mm hex head nuts
Four grade 8 steel washers

Procedure

Weld one bracket to the frame on the driver's side (left) just in front of the leaf spring shackle, weld the other bracket in front of the lower shock mount on the rear axle, brush paint the brackets with black Hammerite, and bolt everything into place. Weld the threaded extensions of the traction bar to keep it at a fixed length (mine is 26.5" from eye to eye) so that articulation is only at the heim joints.

Result

The traction bar triangulates with the rear spring and axle forming an effective axle wrap prevention system. It's not quite as effective as a ladder bar but it has the advantages of simplicity and less weight (10lb all components).
Since I installed this traction bar, wheel hop has been absent so that's proof enough for me that this system works.