Clunk coming from the back, when shifting

04' KJ, 157,000 miles, automatic transmission. Sometimes makes a loud clunk, when it shifts into second gear. Especially if I let off the gas, right after it goes into second gear.
Seems to get worse, after driving a few miles...

Please tell me it's just a worn U joint.
If not what else can it be?

Thanks in advance!

Check the rear upper control arm bushings and balljoint.

x2. Each time I've had U joints go in the KJ, they've make a squeaky sound when backing up.

same thing happened to me 2 weeks ago. felt like a kick in the rear diff. dealer did a transmission reprogram - and a new trans oil filter. problem solved

here -

http://www.jeepkj.com/forum/f196/am-i-headed-transmission-rebuild-62372/

It sounds like it's coming from the right rear. I will check there first. Thanks.

Yes, I believe that is whats worn. One of rubber bushings is shot. Looks like a big pain to replace it myself. I've been driving it that way all winter, and it's slowly getting worse.
I'm waiting for warmer weather, to take another look at it. Guess I need to replace the entire thing?

Yo, my 03 liberty sport // 4wd 3.7 would do this when it shifts.. Kick from the rear, shift funny, or when I am slowly rolling to a stop it lurched forward when shifting as I stopped...

Dropped the transmission pan, changed filter, cleaned out pan, and used a pump to suck all the ****** fluid from the top of the engine out....

Took it in to get a transmission re-learn done, and problem solved!!! (so far)

9 times out of ten its the rear tri-link
Have seen many complain of the same thing only to install a new tri-link and it takes care of it
More than likely why I have 15-18 tri-links piled up

I have the same issue but it only happens in the morning/next day . Once i take off when it goes from 1st to second gear it clunks hard unless i help it by giving it more throttle to slowly shift into gear. After that its all warmed up an no issues for the rest of the day. I also tried doing a longer warm up and that helps too.
I need to do my ****** and diff. Fluid change And see if that helps.

metalmoto said:

04' KJ, 157,000 miles, automatic transmission. Sometimes makes a loud clunk, when it shifts into second gear. Especially if I let off the gas, right after it goes into second gear.
Seems to get worse, after driving a few miles...

Please tell me it's just a worn U joint.
If not what else can it be?

Thanks in advance!

Click to expand...

Hi
did you find the solution for this problem
My car does the same
Liberty 2012 model
Thank you

It cannot be the tri-link on a 2012 because it doesn’t have one. I would check your control arm bushings to make sure they’re ok. Also see if the U joint on the drive shaft is super hot after driving (indicates U joint needs replacing). Also check your motor mounts for play. I would rule out these these things first before trying to bring the transmission into it.