Diff and Gearbox seal help please

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DrGonzoPOW
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Post Fri Jun 15, 2012 11:26 pm

Well, after my van blowing up and then me crashing my E21, now is a good time to delve into the seedy world of the E30's. Bought myself one today....a 318, so nothing amazing but its pretty nice and im already really impressed with it.

Aaha! But for cheap, cheap, something was bound to be wrong. On having a good look underneath the car i could see that there was a fair bit of oil on the diff, and on the gearbox output. So....

How big of a job is it to change the seals and what parts am i going to need please ??? Ive tinkered around with a fair few cars but never really had the pleasure of diff and gearbox work.

Any advice you can give me would be massively appreciated (not general/random advice like, dont wee into the wind or that kind of thing) Ta!

Pic of motor...
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mark_i
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Post Fri Jun 15, 2012 11:53 pm

on the gearbox, you may find that the oil leak is from the selector shaft as opposed to the output shaft. can be replaced if you lower the gearbox on a trolley jack.
on the diff, the drive shaft seals can be replaced with the rear end on stands.
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Billwill
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Post Sat Jun 16, 2012 10:03 am

What model 318 is it....M40?
On the M40 you can replace both rear gearbox seals with the gearbox still in the vehicle but I would not like to try it myself.

The selector shaft can be changed fairly easy with the gearbox still attached and as mark_i has stated this is normally the main culprit.

Look up part numbers on www.realoem.com
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DrGonzoPOW
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Post Sat Jun 16, 2012 6:00 pm

Cool thanks for advice. Could you tell me which seals i will be needing please ? I have had a look on realoem but am unsure of what to get. I know ill need the main seals but i assume other bits will need replacing at the same time ?

Just been having a good look around the car now its dry. Other than a bit on the sill which has been covered up for some reason (which worries me) and the front right wing being flakey at the bottom its not looking so bad body wise. Its had a respray at somepoint thought so it could be hiding many exciting things.

p.s. And yeah, its an Early M40 far as i can tell. Not clued up on E30's just yet
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toby
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Post Sat Jun 16, 2012 8:31 pm

Tap the last 7 digits of your chassis number into realoem and you'll then be looking mostly at the right parts for your car. Check that the bushes for gearbox and diff are OK but other than that you only need to replace the seals that are leaking.
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