Jeep Cherokee Expedition Rig - 8.8 Rear Axle Swap
Jeep guys are always looking for new ways to get better performance or strength out of their setups. Axles are a very big deal when looking at upgrade consideratons, and for an XJ and TJ, the Ford 8.8 rear axle is a very good upgrade. It's super strong, readily available (for cheap), and they are near a bolt in! The track width is a little less than the Dana 35 that they come with from the factory, about an inch per side. No big deal. Another cool thing is they can be found with a limited slip from the factory, too! Some say they are too weak, but from what I have been told, as long as the tire size is moderate, the LSD is plenty strong.
We sourced a used 8.8 out a Ford Explorer from the late 90's so it has disc brakes. We went for an open diff, because we will be installing a locker of sorts down the road. For now, we just want to get the axle under the Cherokee.
First order of business, clean this thing up, cut off all the factory garbage that we don't need, and then make and weld on the stuff we do need! After a little while of cutting and grinding, we now have a clean axle in which to mold into what we need to mount it to the Cherokee.
Since we are currently leaving the rear leaf springs in place, the swap is very easy. Basically, you just need to:
- Cut off the old junk
- Make or purchase new spring perches to weld onto the new axle
- Get new U-bolts the appropriate length
- Make new shock mounts
- Run new brake lines
Easy enough. So we propped up the back of the Cherokee so we could move things around as we needed, and we had to remove that pitiful Dana 35. For springs, the factory ones were rather soft, so we wanted something a bit stiffer, especially considering that we were going to be using this as an expedition rig.
For springs, we used the main leaf from the XJ, and took a Chevy S10 spring back and removed all but the main leaf and stuck it on the XJ main leaf. It lifted it probably 4-5" and it was nice and stiff, but not too stiff. Since, at the time, we are using the Cherokee as a tow rig, we left the overload spring in the pack as well, with possible plans to remove it down the road. We repainted the springs and attacked them.
The factory pack was so bad because, once we pulled them apart, we discovered one of the leaves had broken!
After we installed the axle, we made some new brake lines for the axle, and replaced the flexible line with a new one also.