On my 1998 Cherokee 4L 4wd when I am in reverse then put it in drive there is a clunking sound. I was told it needs a new u joint. Then yesterday I put on new tires and on the way home it started to make a thumping sound. It kicks in at low rpms and increases as the rpms increase then slows down as the rpms slow down. Could all this be from that u joint? I grabbed the haft and it can be rotated back and forth. It also has a front brake pad that is getting into and scoring the rotor.

 

Could be your transmission mount. Mine was bad, and I threw a bunch of u-joints at it to no avail. Switched out the mount and it fixed it. It was bad enough that it felt like something knocking on the floor under my feet.

It's a pretty easy thing to just throw on. They're like $30-40 if I remember correctly. Just put a jack or something under your transfer case/transmission to support it, then take the four bolt out of the center of the crossmember (13mm??) then remove the four bolts holding the crossmember to the frame rails (15mm??). Then I believe there are four bolts holding the mount to the transmission. Slap the new one on and bolt it all back together. If you're not too rusty it should be no sweat.

 

The Transmission crossmember had been hit in the past and the mount was deteriorated. Got a crossmember from the salvage yard and new mount so now it runs like new-thanks

 

Cool beans