M60 Gearbox flanges

[Darrenr]

Hi,

Ive had m60 in my e30 for over a year now and cant seem to get my gearbox flange right im using a 2.5 flange mated to the m60 box, after a while it starts to leak, what do other people use and anyone ever had any leak problems?

thanks

[Jonsku]

What part do you actually mean by "gearbox flange"?

Alignment problems, maybe?

[Darrenr]

i mean the metal flange with the single bolt thats bolts it to shaft on gearbox mine seems to pass oil

[bongo78]

Thats pretty normal, on all my swaps - M20,M50,M52 I have always replaced the little shaft seal on the transmissions and after a while they all started to leak a little :) . If it is really small leak just ignored, if you haven't changed the seal change it, it will be ok for a while :) . The flange you mention has to be as level as possible to prevent leaks. IMHO

By "gearbox flange" you mean number 4 in the diagram?



The leaking starts from number 7 on the gearbox:

[Darrenr]

Ive now changed seal 7-8 but still thought ut may be passing through splines, i keep getting told there wouldnt be enough oil so high up in the box to leak that much?

[bongo78]

You have done whats needed already :) , the leak should have stopped. If you have changed them correctly no leaking from the splines should occur. That is correct, that high you only get splashes inside the gearbox. As I told you, I have stopped changing the small seal n7, the leak itself is so small it doesn't affect anything, just the visual side of the things :)

[JGood]

Apparently BMW uses a special grease on the splines that prevents leaking. In addition, apparently it's possible for the output flange to see some wear, right where the seal is, which could also cause leaks.

I've had terrible luck doing output shaft seals on g260's and zf320's. Which is why I didn't touch my ZF before I put it in my m60 car.


Here's a thread where some local guys and myself were discussing it:

http://www.r3vlimited.com/board/showthread.php?t=86005

[Darrenr]

thanks for that info, this is what i thought mine is doing, leaking through the splines i sealed it tonight to see if it works also changed selector seal just to see if that will help

Its when im on a track its not allowed and track owners aint to happy, So i have to sort it really

[Darrenr]

i put a new output shaft seal in the other day it lasted 2 laps and started leaking again! its 100% leaking out the bottom of the seal and not the splines any had the same problem is there any fixes?

thanks

[CoreyZ]

It sounds like you are talking about the output flange - the flange that connects the transmission output shaft with the driveshaft through the flex disc. Is this correct? You were able to bolt one of the six cylinder flanges to the gearbox? That might be your problem - the outer diameter of the flange where it meets the seal might be too small.

[Darrenr]

Yea thats the one im on about, the 3 bolt flange that connects to the rubber donut, ive got a 2.5 flange bolted to a 6bolt rubber "donut" i took the flange to the shop and got a slightly smaller seal than the bmw one but still the same external size but still leaks just woundering if anyone has a fix

[Darrenr]

ive poped a new seal in and last 2 laps, im using a e30 325 flange and prop.... what does everyone else use?

[Jonsku]

ive poped a new seal in and last 2 laps, im using a e30 325 flange and prop.... what does everyone else use?

We use stock gearbox flanges, seem to be pretty sensitive..

I propose that you'd put the stock flange back (with new OEM seal) and modify the propshaft. This would give you more durable 'shaft as well.