Over the last two or three years I’ve experienced a clunk / thud noise coming out of the transmission / drivetrain somewhere when the transmission isn’t under load and when gently applying power. It tends to be erratic but nearly always occurs when the vehicle is freewheeling and then power is applied. Changed the transmission mount recently and the engine mounts are all OK. I’m at a lost to where this is coming from?
-
-
I had something similar. Turns out it was the front driveshaft CV joint transfer case end. Try driving with front driveshaft off - don't worry is safe to do so as Jeep AWD systems runs in 100% RWD bias in good traction. -
Has anybody messed with the engine tune? I had a play with this when I owned a WG CRD. The factory tune in 4H still keeps a little fuel flowing at zero throttle. This keeps a small positive torque. I tried taking this out and got a massive driveline clunk as a result, so I put it back in.
Footnote - The above is only in 4H. In 4L zero throttle position is always zero fuel, until the idle routine kicks in (from memory around 1000rpm).Comment
-
Yes, that has happened to me (and still happening to less degree). What I think most likely is it's play in drivetrain. I get the clunk when going from low load to high load on the drivetrain, for example accelerating hard or braking hard.Originally posted by Lecia-user View Post
I also had weird vibrations when cruising or on mild accelerating. My front driveshaft had quite a bit of play so I decided to take out the differential cover and found a ton of play between spider gears, spider gear shaft and spider gear to axle splines.
Bought a spider gear rebuild kit and new front axles. Problem solved after that. I still have to rebuild rear diff since I can hear some bearing howl noise when accelerating and found a minor leak on the pinion seal.
Take this checklist as a guide for diagnosing it:- Check suspension and steering components for play, just in case, but I don't think the clunk will be coming from there
- Put your transfer case in 4LO so it locks front driveshaft and check the driveshafts. Move the shaft against the shaft joints, there should be minimal to no play at all.
- Check driveshaft yokes play, up and down and side to side. There should be no play at all. I have very minimal up/down play on the front transfer case yoke which I think it might be normal, anyway it's not causing problems.
- Take out 4LO, rotate the driveshafts to check differential backlash, there should be minimal play, you should hear a faint "clunk", that's the normal play between ring a pinion. If you can hear this clunk, but then you can rotate it further, then there's play in the rest of the diff and axles, open for inspection and follow previous video.
- If you still can't find where the clunk comes from, remove the front driveshaft (completely safe) and try to reproduce the problem without it. You will isolate the rearend by doing this.
Comment
-
Many moons ago in mine it was the front shaft CV that was on the way out, replaced with a Ford BA ute CV and all good ...............2015 WK2 Laredo(ZG, WG)
Never too old to learn something stupidComment
-
Excat same issue with mine. Most likley OP has this issue.Originally posted by drover View PostComment
Comment