96 "thunk" in rear

[Travis Messenger]

I just purchase a 96 XLT w/60K on it. Its a 5sp w/V6.
I didn't notice on test drive, but everyonce in awhile there is a thunk coming from the rear end. I don't think it is the U-joint, because it doesn't seem to correspond to torque on the driveshaft(letting off gas in 1st gear) I was wondering if it could be the shocks(original) or the sway bar bushings. How do I go about diagnosing this problem. I don't like to let things go too long.

Thanks
Travis

 

[JoshC]

Well, it could be many things Travis. Give us some more details. Like, when does it do it, during braking, flexing, acceleration. That way we can narrow it down a little bit!

Happy trails!!

 

[Travis Messenger]

Sorry about that.
The noise doesn’t seem to correspond to any one thing.
I hear it sometimes when I start out and also when stopping.
I hear it when going over bumps, big and small, but not every time.
I also hear it when pulling into my driveway and the X rocks sideways.
I think it may be a sway arm bushing because it seems like it is related to the flex of the rear end. But it also could be the shocks because they look like the original. I also hear a similar noise from the front end, but not as often.
Thanks for any help on finding this problem.

Travis

 

[MyExpWork]

Its gotta be the slip yoke in the driveshaft. My 91 made that noise. Going over speed bumps (sometimes), coming to a stop (sometimes) starting from a stop (sometimes).

I changed all shocks (they were old), didn't help. Finally I read on here that the slip yoke can bind and cause this noise. So I pulled the driveshaft from the tranny, seperated it at the slip yoke, cleaned it and relubed with grease.

Problem solved. Its been about a year and its starting to come back a little though. May be time to do it again.

Brian