BMW E92 Diff

[RECampbell]

I have a constant sound from my rear diff on my 318i Coupe.
It has only done 70,000 miles.
Any advice?

[naturalaspiration]

Try adding LM Ceratec - 8% of the filling capacity.

[Touring442]

RECampbell said:

I have a constant sound from my rear diff on my 318i Coupe.
It has only done 70,000 miles.
Any advice?

Yes, it's knackered. The pinion bearings fail - some go at 50k, some last 200k or more depending on who made the bearings. I always have good E90 and 1 Series diffs and have one for that. You're looking at 300 quid for a good used one, or to rebuild yours, a £120 bearing kit and a lot of aggro assuming the crownwheel and pinion aren't damaged.

Ceratec will do nothing.

It's about 1.5 hours to replace the diff.

Oddly enough, I was rebuilding a 118d diff this morning. This is what awaited me:

[RECampbell]

Thanks for that. I'm getting it checked out tomorrow, so I hope it won't break the bank.

[Touring442]

Where are you based?

[RECampbell]

Northampton

[Touring442]

What was the outcome?

[RECampbell]

I had new bearings etc fitted at a local garage that specialises in BMWs for £800 all in, as opposed to £2000-£3000 estimate from Main Dealer.