Rear knocking, last straw.

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ianeire
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Post Wed Nov 08, 2006 7:30 pm

Howdy guys,

Ive a knocking coming from the middle/rear of the car when cornering to the left and over bumpy roads occasionally. It doesnt manifest itself through every left turn and depends on the angle of the corner and the speed carried through it.

It is not the top mount. Ive had them changed.

It is not the subframe bushes, ive had the diff out and about and it doesnt hang low etc.

It was serviced today and the garage reckoned it is not trailing arm bushes.

Sitting in the car when it occurs it seems to be coming from under the back seat to the left of the prop shaft, and when it happens, it is loud. It's certainly not one of those noises that I the owner hear.

Any idea???? What are the symptoms of an ARB link gone or ARB dammage?? If the ARB was damaged would the symptoms manifest themselves going in both directions as the bar flex's??

I'm perplexed. Help.
Last edited by ianeire on Wed Nov 08, 2006 7:52 pm, edited 1 time in total.
1990 Brilliantred 325i Sport

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Post Wed Nov 08, 2006 7:47 pm

Have you checked the petrol tank to see if any of the bolts are missing ??? Have seen this on a different brand of car. Unlikley but worth a look..
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ianeire
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Location: Cork, Ireland

Post Wed Nov 08, 2006 7:51 pm

Hmmm, now thats something that has never occurred to me.

Is there anything down along the length of the prop shaft that might go?

Its not the big diff bushing or the exhaust either....
1990 Brilliantred 325i Sport

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harry_p
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Post Wed Nov 08, 2006 7:54 pm

could be an antiroll bar mount. when the car turns one way the arm twists one way, when it rolls the other way it twists the other way.

had it on a previous car where the mount cracked away from the floorpan, the left hand mount was cracked, and the bar would knock when you turned right as the car rolled to the left and pushed the mount back to where it should be. worth a look for sure.

oh, and go for a short drive with all the tools, spare wheel and jack removed just to make sure its nothing silly.