Clunk in the back end!

[Michael_M]

Hi everyone,

I had something going on with me Ti lately, whenever I accelerate and let go the gas pedal fast I hear a clunk sound from the rear.. Seems more to be coming from the right side but I'm not sure, I didn't lift the car up yet to check anything but was wondering what might be causing that..

Do you think it is something in the drivetrain or loose suspension parts (maybe bad bushings?)

Also there is a whining noise coming from the back when driving above 70kmph.. I think it may be a wheel bearings that went bad but anything else muse cause that ? it ain't loud tho but I'm sensitive to my cars so I can differentiate different noises and if they're weird or not!

Thanks for the help

[Biolite]

I'd check your subframe bushings, exhaust hangers, and trailing arm bushings first. I think any of those may be a good culprit. I've also seen springs and rear shock mounts break and cause a clunking on one side like that.

[spidertri]

You should check out everything that Biolite suggested.

Even after replacing all the bushings and suspension stuff there are still clunks and creaks that this style suspension seems to make. The whining noise could be the differential. Doesn't necessarily mean it is going to fail, a light whine is probably normal gear noise.

[Wouter1981]

Originally Posted by Michael_M

Hi everyone,

I had something going on with me Ti lately, whenever I accelerate and let go the gas pedal fast I hear a clunk sound from the rear.. Seems more to be coming from the right side but I'm not sure, I didn't lift the car up yet to check anything but was wondering what might be causing that..

Do you think it is something in the drivetrain or loose suspension parts (maybe bad bushings?)

Also there is a whining noise coming from the back when driving above 70kmph.. I think it may be a wheel bearings that went bad but anything else muse cause that ? it ain't loud tho but I'm sensitive to my cars so I can differentiate different noises and if they're weird or not!

Thanks for the help

Hi, may I jump into this threath because I have something similar. Does the rear clunk when you are manouvring your car around? Mine almost everytime I depres or engage the clutch. And when driving 110 in 5th and a get on and off the gas, I hear the clunc every time. Does your car do it also?

[1996 328ti]

Diff U-joint?
Center Load Bearing?
Guibo?

[Michael_M]

It turned out to be loose suspension. Tightened it up and no ore clunking noise.. for some reason it seems you need to tighten them with every oil change (8k kms) just to make sure!

[Wouter1981]

Originally Posted by Michael_M

It turned out to be loose suspension. Tightened it up and no ore clunking noise.. for some reason it seems you need to tighten them with every oil change (8k kms) just to make sure!

What do you mean with a loose suspension. Just soms overal slopiness, or some bolts specific that were loose?

[Michael_M]

It was the rear subframe bolts, mainly the right side that connects the subframe to the chassis, but oddly enough the left side was a little bit loose also

[1996 328ti]

Originally Posted by Michael_M

It was the rear subframe bolts, mainly the right side that connects the subframe to the chassis, but oddly enough the left side was a little bit loose also

That just is not normal.
Do you have aftermarket bushings?

[Michael_M]

Nope, just the stock ones!

[Wouter1981]

Can I ressurect a little thread?
I have a similar clunck that can be heard when going on and of the accelerator. Almost every bushing has been replaced but the clunking remains. But I recently discovered that it's somehow related to the weather! The wetter the weather, the more I hear the clunck. When it's bone dry I just can't produce the clunck, no matter how violently I try but when it's soaking wet, I hear it a lot. Does anybody has an idea?

gr
W

[3.2TI]

Check your diff fluid level, bushing and bolts. These are fairly common issues related to rear clunk, at least on my car with s52 and 3.73LSD.

[Wouter1981]

I have swapped my diff with a LSD diff from a Z3 and I've used a new bushing and bolt. The clunck remained the same so it's definatly not the diff.

[spidertri]

There is a certain amount of backlash between the pinion and ring gears, I can get a clunk in the driveline from that backlash. It is very common on the old bmw diffs.

[Wouter1981]

I don't think it has anything to do with the diff because the clunk was identical after i switched to a LSD diff.