Propshaft/Differential Noise

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Lemon98
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Post Fri May 08, 2020 9:26 am

I car has recently developed a whine/rubbing sort of noise which sounds like it's coming from the propshaft somewhere but also if you turn a driveshaft with the rear end in the air there's a definite clunking sound from the diff. The diff noise goes once I start the car and put it into gear.

Am wondering if anyone has had this noise before and can point in the right direction of things to check.

It's an 80k mile 320i with open smallcase diff which I do occasionally do wheelspins in. Recent oil change as well. Poly Diff bush went in, did a one wheel peel and then BOOM the noise started. Subframe bushes need changing.

Here are the links to the videos:

1990 4-door 320i SE
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Brianmoooore
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Post Fri May 08, 2020 10:52 am

The sound on that video is just like that made by our old 1950's Lister electricity generating set! Doesn't give me any clues at all.
Clunks can be caused by the failure of the mount for the prop. centre bearing, whines tend to be the diff. input bearing, and scrapping noises are often simply rust under the dust covers on the diff. output shafts.
Or, of course, you could simply have bu**ered your diff.
Drain the oil out of it and inspect it. Large chunks of metal in it is not good.
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paultv
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Post Fri May 08, 2020 4:38 pm

The diff will clunk when waggled with the wheels - there's some backlash - it sounds louder as you put the phone further under - sounds daft but
check the metal dust shield which protects the input shaft seal where the prop enters the box - if bent it will scrape and make an 'orrible noise.

Long shot but worth a look

Paul :-)
4th May 1990 325i Convertible.

BMW E30 Cabriolet Best Mod Ever:

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