jeeptec
NAXJA Forum User
- Location
- atascadero california
2000 Xj. 4.0 automatic. 242 tfc. Dana 30/ 8 1/4 .I have a vibration from 60 to 72mph. It is somewhat oscillating. I noticed it after I lifted from 3 to 4.5 inches but at the same time in did rear disc brakes from a grand cherokee. An Aussie locker. I ordered and installed an Iron rock hack tap for my 242 tfc. A Tom Woods shaft set drive line angle no change.i found a bad rear pinion bearing . I did my gear swap to 4.10s. No change.took out front from driveline no change. Changed trans mount no change. Re balanced and rotated tires.no change. Set Tom Woods driveline back for Re balanceing.it had a bad ball socket. No change. Tried another driveline from another Jeep. No change. Install 2 degree shims to lower pinion and raise pinion. No change. I ran the jeep on the drive on rack using the air jack under the rear axle.did not find excessive driveline run out. Looked for grounded out engine mounts there worn but ok. Looked for exhaust sitting on body or crossmember. All ok. Not sure what to do next.