Noisy rear diff

[T-man]

Any idea how to rid the noise?
Tried changing the fluid?

E30 325i 1987

Regards

[Dave_M3]

What sort of noise?

Clunking, whining, or sort of churning noise?

Usually, it's a bearing or the lash is not set correctly

[Chris-W]

More pronounced when coming off throttle or on?

[tomson]

Any idea how to rid the noise?

Get a new diff, if it's not a LSD £50 will find you a decent non leaky one.

[wildeian]

Aha!! I'm having trouble too!

How much backlash should there be? (LSD) I have about 2 cm of circumferential tyre movement between teeth. Feels a bit too much to me!!??


I'm guessing its gonna be a strip the diff job too?

[adit]

are iS diffs different to standard 318 diffs?

[Dave_M3]

Aha!! I'm having trouble too!

How much backlash should there be? (LSD) I have about 2 cm of circumferential tyre movement between teeth. Feels a bit too much to me!!??

Yeah, 2cm is too much.

I'm guessing its gonna be a strip the diff job too?

It's not overly difficult. Requires pulling out the out-put shafts,
Taking off the flange and machining the shims/spacers that are between these and the diff casing.

Looking at diff from back cover, thinner spacer needed on the left, thicker on the right.

This enables the bearings, crown-wheel and LSD unit all to move closer to the pinion hence removing the lash.

There should be about 1.5mm of lash in the diff without oil. The oil will then take up the remaining lash.