1996 Jeep Cherokee mileage: 62,000. I am experiencing 'bump' on acceleration and deceleration. It feels like a badly worn U-joint or excess play in differential. Upon the advice of Jeep dealership, I lubricated rear drive shaft slip yoke, no improvement. I had the differential inspected by a transmission shop and I was told actual gear lash =.010", spec =.008" to.012". I had the drive shaft checked for balance it was okay. I had rear the drive shaft slip yoke checked for wear and it was okay. I had the rear drive shaft U-joints checked and it was. I had the transfer case pulled and inspected by transmission shop and they replaced questionable bearing on main shaft. The problem was gone for a week, but then it came back. I had test drives performed by three transmission shops and they all said the transmission is okay. I had the brakes checked by two brake shops and of them both said the brakes were adjusted and working properly. Three mechanics indicated a problem due to axle 'spin', advised new shocks. I replaced shocks and no improvement. I test drove another 1996 Cherokee at the dealership and it had the same problem, but much less pronounced. Is this typical of later model Cherokees? I have driven a 1990 Cherokee for 160,000 miles and a 1988 Comanche for 50,000 miles, both 4.0L, auto, 4WD and I never experienced anything like this with either vehicle. Any ideas on how to rectify?
Here are some things you might check: 1. The bushings in the suspension may be worn out allowing movement. 2. Possible motor mounts are worn allowing the engine and transmission to shift. 3. The clearance on the exhaust pipes should be checked to see if they are too close to the frame.