Knocking noise

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Tripper
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Mon Mar 29, 2010 9:19 am

I have knocking noise coming while driving, it gets louder as speed increases what can this be..? :?

It also does this when turning around corners... I have been told that it could be a bearing..? how can you tell which wheel could this be??
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Paul325ITouring
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Mon Mar 29, 2010 10:02 pm

Hi it could be a the diff m8 is the noise more from the back? I had the same and it was a worn diff, try jacking up the car and spining, each wheel.
jmc330i
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Tue Mar 30, 2010 10:35 am

A duff wheel bearing wont give a knocking noise, more of a rumble. The rumble can get more noticeable whilst turning.
You may be able to hear it if you jack up each wheel and turn by hand or pull the wheel top and bottom to find any play in the bearing.
When is the MOT due - if a wheel bearing is shot, the tester should pick it up.

If its a knocking noise that gets louder with more speed, Id get the prop centre bearing checked.
James
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Messenjah
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Tue Mar 30, 2010 11:00 am

Cv joint is also another good bet ..


gets worse on acceleration and almost goes decelerating ?



diff or cv joints is my bet and if the diff is that shagged youll need a new uj on the prop
Tripper
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Tue Mar 30, 2010 11:29 am

Guys this sounds expensive
jmc330i
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Tue Mar 30, 2010 11:45 am

Not really.
Wheel bearing (front) can be had for £30-£50 plus fitting - should be no more than hour at a decent garage. Rear bearings are cheaper to buy, but can be more difficult to fit.
Prop centre bearings are around £20-£30 -again an hour should do it.

Unless the diff has been run low on oil or abused a lot, I doubt it will give much of a problem. Most knocking noises associated with diffs are down to a knackered diff mount bush.
Even if the diff is knackered, an open diff will be easy to find and usually cheap as everyone wants the LSDs.

Can you describe the noise better?
Is it a knocking or rumbling? Does it happen all the time whilst on the move or just a single knock every now and again (when turning for example)?
James
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'93 318i touring 16v
Tripper
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Tue Mar 30, 2010 12:56 pm

Sometimes driving along I dont hear anything, when the speed is up 40mph+ the rumbling gets louder.. louder when driving round corners... :(
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ProToZyKo
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Tue Mar 30, 2010 1:27 pm

Sounds like wheel bearings, does the sound get louder when turning left or right?
m_jermyn
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Tue Mar 30, 2010 1:30 pm

Are your wheels on nice and tight? I had the same issue and I checked the wheel nuts and they where just a little loose.. Nip em up and nocking went away...
jmc330i
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Tue Mar 30, 2010 1:57 pm

Tripper wrote:Sometimes driving along I dont hear anything, when the speed is up 40mph+ the rumbling gets louder.. louder when driving round corners... :(
Could be a wheel bearing, more than likely a front one. Should be no more than £100 all in for a garage to do it and thats with a quality bearing.
If youve got access to a 36mm (IIRC) socket, a torque wrench and a decent hub puller, you should be able to DIY it.

Loose wheel nuts could also be an issue.
James
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ProToZyKo
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Tue Mar 30, 2010 10:37 pm

I feel like loose wheel nuts sounds more like a "flat tire" and you feel it on the steering, but it would be a good idea just to check. Has happen to me 2 times, first time it took a while before i knew what it was, just cached it in time.
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