So after taking the Cherokee out off-roading the other day, I noticed a clunking noise coming from the rear of the vehicle during braking. The speed of the clunk was directly correlative with the speed of the vehicle, slowing as the vehicle did. It was not clunking on acceleration.

Well, since I had no idea when the rear brakes were last done, I went and got all the fixings to correct the problem, and replaced the rear pads, hardware, and had the drums turned. After everything was buttoned up and adjusted, I took the vehicle out for a test drive...and the blasted clunk was still there. In addition, now I noticed it under acceleration, but only up to about 10mph or so. I can't hear it at all while driving down the road.

Any ideas? I tried checking out my driveshaft, and there's very little side to side movement...maybe an 1/8", at the most. I haven't had a chance to check it yet, but I was thinking maybe a tranny or engine mount going bad?

 

rear carrier bearings ?

 

I would check you wheel bearings, if it was Carrier bearing I think you would be more prone to here it when there is a change in torque load.


You also said "after taking the out Cherokee off roading" ...don't do that you might brake something.

 

Well, it's not the first time it's been offroad, and I've never really had a problem with it. This time was a doozy, though...not only did I end up with this clunk, but the Jeep started overheating badly (that's getting changed today).

I know how to check the wheel bearings, but how about the carrier bearings?

 

Check the U-Bolts on the springs.

 

Ubolts are tight, and as tight as they're going to be.

 

IMO its a u joint or maybe even a bad spring on the rear brakes. Did you get a new spring kit when you changed them? ...Tj

 

could be a broken tooth on the diff ring... raise the jeep rear and tiurn the shaft by hand.

 

When I did the rear brakes, everything was replaced except the wheel cylinder. New springs and parts on both sides, new pads, turned rotors. Now that I'm hearing it on acceleration, I realize it's not a brake issue...but they definitely needed to be replaced anyway. I had no adjuster cables on either brake, and there were other parts missing, too. I checked the driveshaft, and the u-joints seemed solid. There was no wiggling up, down, left or right, and the rotational slop on the driveshaft was minimal. It's a 1995, so I know it's not a dry slip joint, either.

When I had the rear end jacked up, I turned both axles by hand...they seemed smooth enough, but I could hear and mostly feel a light 'tuckita-tuckita-tuckita-etc.' noise/vibration. I haven't replaced the fluid inside the diff yet, so I'll pop the cover off and take a look inside to see if anything is amiss.

 

Alright, an update. I opened the hood to drain my radiator in preparation for a flush, and while laying on my back underneath the vehicle, I happened to look up at the mechanical fan. Holy crap, it's embedded into the fan shroud a good 1/2" or so...it's missing a nice chunk of metal by about 1/16", if that. I took a look at my motor mounts, and they're pretty much destroyed. I wouldn't be surprised if my transmission mount was, as well.

While it could be unrelated to my rear-end noise, I could definitely see the motor and tranny moving around under braking or acceleration as causing driveline angle issues and creating the noise.

Thoughts?

 

the klunk in the rear could be the TC hitting somewhere due to the bad mounts

 

That's what I was thinking, since the tranny mount is definitely trashed. I'm also thinking that sudden deceleration or acceleration is causing the whole engine/tranny package to move enough that the u-joints are starting to bind up, causing the noise as well. Time for new engine and tranny mounts!