Front suspension clonk

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MarkS100
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Post Mon Nov 10, 2014 5:06 pm

Hi all,

I wonder if you can help with the following problem. I have had my 320i cabby for about 3 years and no serious problems in that time. The previous owner had it lowered by 40mm. A year or so back a local garage replaced the steering rack and front dampers. All seemed OK for a short while, but now the front suspension makes quite a severs clonk as it goes over speed bumps and similar obstructions.

The last MOT didn't reveal anything obviously loose.

My suspicion (and I could be completely wrong!) is that the dampers may be don't match the lower springs.

Should I buy different dampers and/or can I check the new dampers to see if they are suitable before I go ahead and get some new ones.

Many thanks,

Mark S.
HairyScreech
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Post Mon Nov 10, 2014 5:13 pm

Top mount bearings?
2.8 development thread http://www.e30zone.net/modules.php?name ... c&t=170822

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milescook
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Post Mon Nov 10, 2014 5:19 pm

Is the top mount nut properly tight? A loose one as well as the above (I've had two on different cars) gives a distinct clonking noise over obstacles.
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Grrrmachine
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Post Mon Nov 10, 2014 6:02 pm

Simplest thing is to jack each side up on jack stands, and give the wheel a vigorous wiggle. You should be able to feel where the play is.
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Brianmoooore
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Post Mon Nov 10, 2014 6:43 pm

milescook wrote:Is the top mount nut properly tight? A loose one as well as the above (I've had two on different cars) gives a distinct clonking noise over obstacles.
This is probably the most likely, since they've been disturbed.
Remove the black plastic cap on the top of each leg under the bonnet, and compare the lengths of thread showing through the nut.
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MarkS100
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Post Tue Nov 11, 2014 11:13 am

Folks,

Many thanks for the feedback. I'll check out the state of the top mounts and see what I find.

Regards,

Mark S.