I have a 2000 cherokee Classic with around 150k miles. I have been hearing a "groaning" sound coming from the rear of the vehicle when I accelerate from a dead stop. It seems more prevalent after I have been travelling at a contsant speed of around 50 mph and up. I thought it was my rear brakes not releasing prroperly, but they have been replaced. the sound is still there. Could this be something in the rear differential?? Any ideas?? Thanks.

could be ujoints or trans rubber mount broken.

Check what 89ltd said. If those are ok, could be a wheel bearing or the carrier bearings in the diff. At the speed you describe, it's not likely that its the pinion bearings.....

JD

Check what 89ltd said. If those are ok, could be a wheel bearing or the carrier bearings in the diff. At the speed you describe, it's not likely that its the pinion bearings.....

JD
Thanks for your help!--It turns out to have been the drive axle needing lubrication.