Diff noise

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jonbuoy
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Post Sun Jul 31, 2005 5:21 pm

I have a slight problem...........just when i'm pulling away or reversing or also just coast at about 10ish mph i get a slight grinding noise from the rear of the car. Thought it might be the bearings but i've checked it all out and seems to be fine, it only happens when the diff is slack. When i engage into gear again and then drive the noise goes away. Its a horrible sound, i put some new oil in it today, heavy duty, and its still there.Has anyone experienced this problem?

Fcuked Yes/No

And also does anyone have a lsd that will fit? M40 318i
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Ant
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Post Sun Jul 31, 2005 5:29 pm

small case diffs are rare as hens teeth dude, best bet convert to 3.91LSD big casing from a sport, plenty about again, M40 will just pull that ratio too but accel will be blunted a tad

what you are describing sounds like a defective propshaft coupling . U/J and driveline slack will announce itself as a clunk on taking up drive.

get the joints checked and pay particular attention to the rear diff mounting in the rear cover, it would not be the first one to fail and can cause similar problems to what you're describing.

HTH

typos edited :lol:
Last edited by Ant on Sun Jul 31, 2005 7:18 pm, edited 1 time in total.
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jonbuoy
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Post Sun Jul 31, 2005 6:05 pm

Cheers mate much appreciated. I do get the initial clunk first of all, do you know anyone with an lsd and what sort of wonger(Ԛ£) am i looking at?
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Lordschleife
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Post Sun Jul 31, 2005 6:35 pm

ant wrote:small case diffs are rare as hens teeth dude, best bet convert to 3.91LSD big casing form a sport, plenty abaout again, M40 will just pull that ratio too but accel will be blunted a tad
You can put slightly smaller tyres on to offset this a bit
eg 205/50/15 instead of 205/55/15
or 195/60/14 (maybe even 195/55/14) instead of 195/65/14
Cheers,
Robin

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jonbuoy
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Post Sun Jul 31, 2005 6:57 pm

Currently running 215/40R17's. Is it hard to shorten the diff if you've never done it before?
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Lordschleife
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Post Sun Jul 31, 2005 7:02 pm

So you'd probably want 215/35/17 then

Should cost you around Ԛ£250 for an LSD
Cheers,
Robin

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