when i take off from a stop, if i get on the gas a little i hear a thud thud thud, then very light vibration til i hit second gear. im thinking its the tailcone sleeve on the transfer case. i have replaced both motor mounts and tranny mount, as well as this sleeve. but i can still move the driveline around in the housing. i have a slip yoke eliminator kit in the mail right now, just wondering if anyone thinks it may be the same thing. it has done this since i have owned the jeep.

 

I have a similar problem. It sounds like a marble is rattling around somewhere in the rear when i idle then it gets louder as i accelerate and stops at second gear. Can anyone help us out?

 

mine is getting worse. it actually vibrates pretty bad if i floor it. im pretty sure its the little sleeve in the transfer case tail housing. i can move the driveline around pretty good up where the slip yoke is. i will see if my sye fixes the problem.

 

Check the exhaust at the crossmember and the tail pipe at the tank.
If you have the stock diagonal TC skid plate that could be too.
Regarding the slip yoke, remove the rear drive shaft and close the TC tail ducktaping a plastic bottle on it. Then put in 4wd high and go test drive.

 

well it fixed it. and i love my new iron rock offroad 6.5 inch lift. now i need bigger tires

 

instead of figuring out the problem you installed a new lift kit? I dont get it.......

 

I think the problem comes from the old lifts...
Its nice to hear that you got it fixed..

 

so instead of figuring out what was wrong with it, bushing or super flex joint he bought a new lift? still makes no sense.

So what was the issue? knowing helps us all because we all have had weird noises from time to time

 

no. the problem was the drivelines slip yoke at the transfer case. i needed a sye when i was going to put my lift on. i was just hoping that the sye would fix the problem. the problem was the bushing inside the tailcone on the transfer case being worn out.