Leaking diff query.

john-e89 · Post by **john-e89** » Sat Oct 03, 2020 7:25 pm

Car is on 38k but has recently developed a pretty bad diff leak, enough to have oil drops and it smeared all over the underneath from air flow, no issues, I can sort it. My question is, does anyone think it’s worth doing any maintenance while it’s out, I’ll be soda blasting and painting it but no plans for anything else due to the mileage. Preload should be fine on these miles no..? No desire to alter the ratio, certainly don’t want it any shorter. I’m thinking just put a new gasket and oil in and that’s that.

Any thoughts...?

Truth · Post by **Truth** » Sat Oct 03, 2020 8:03 pm

Input and output seals, oil, rubber and bolts in the mounts. Apart from blasting and painting I can’t think of out else. Maybe get oil analysed. I just got seals and oil when I bought the car in 2015 and have never had a problem.

john-e89 · Post by **john-e89** » Sun Oct 04, 2020 11:06 am

Truth wrote: ↑Sat Oct 03, 2020 8:03 pm Input and output seals, oil, rubber and bolts in the mounts. Apart from blasting and painting I can’t think of out else. Maybe get oil analysed. I just got seals and oil when I bought the car in 2015 and have never had a problem.

As I thought too. Cheers Mark.

R60BBA · Post by **R60BBA** » Sun Oct 04, 2020 12:55 pm

Replace your input and output shaft seals and put in some fresh BMW Motorsport with FM Booster fluid.

No need to get the diff fluid analysed.

john-e89 · Post by **john-e89** » Mon Oct 05, 2020 4:17 pm

Cheers. Agree no need for an oil analysis on a diff.

Justino · Post by **Justino** » Mon Oct 05, 2020 5:10 pm

Also clean the old oil off - I had all the seals done 3 years ago by a garage, and now when I look underneath I am wondering if I have a fresh leak, or whether its the residue that sprayed onto the floor pan, and up the side of the petrol tank. Its going to be a winter job, up on ramps and clean the fluid off with brake cleaner, and then monitor from there.

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