Vibrations from the front suspension

[victorzu]

Hey there, I was hoping someone might give me some advice on what would be causing the front end of my early '98 523i sedan to make a little clonking noise.

Although the driver can not perceive the noise when behind the wheel, it becomes most noticeable at low speeds on uneven ground; however, it is more of a nuisance than a safety hazard. Both of the vehicle's most recent UK road-worthiness tests (MOTs) included shaker plate inspections, and both passed without incident. The repair personnel have been doing extra thorough inspections in an effort to identify the source of the problem, but thus far, they have been unsuccessful.

The noise didn't start until last year, nine thousand miles after the car had new struts, Sachs road springs, and top mounts installed in 2023, sixteen thousand miles ago. Although the previous ones had very little wear and were within the MOT limits, I still had two authentic BM drop links installed in an unsuccessful effort to fix the issue.

All of the Michelin tires have evenly worn treads, the car has excellent handling and braking, and the mileage is over 180,000.

Much obliged for your time.

[ethan.kellyyq]

Make an effort to simulate the parked car's sound or problem by pressing down on each corner...

[ibrahimwalkerxa]

Yeah, I've been there and done that.

After I changed the strut mounts, the rumbling stopped.

[victorzu]

Thank you for getting back to me so quickly. I take it you mean the top mounts?

Curiously, (a) the noise didn't exist before the suspension overhaul, even though the original top mount bearings were shattered, and (b) you would have assumed that the replacements would last longer than 16,000 miles on a car that isn't driven heavily.

The rubber mount inserts seem to be in good shape, the nuts are tight with paint markings on them, and the towers are not misaligned. I've bounced the car, but it still doesn't sound as it should.

[luna_hugheso]

Are your wheels Bilsteins?
The B8 (sport) is mine. Some time ago, while I was snarled in California traffic, it started making rattling and clanking noises. That was probably about 2022. So far, I haven't had any luck with this in the Seattle area. The only difference that comes to me is that Washington state is cooler than California.

I last gave it a cursory glance a while ago. I think the B8s are backwards (and I think the E30s are also), meaning that the shock's oil and valves are situated on the strut tower, and the casing is similar to a shock cover but made of metal instead of plastic because it needs to hold camber. I have not yet taken it apart to see whether there is any play in the housing (lower strut?). whereas the upper strut and knuckle mounts are still in the works.

[christian_nakamuraf]

In order to silence that noise, I swapped out the bearing in the right upper strut mount on my 2004 BMW E60 530i.

[alice_thomasc]

While navigating uneven pavement in my 2018 X5, I had some severe front end clunking. My transaxle on the passenger side came determined to have a U-joint. It wasn't extremely loose, but the clunking was caused by it.