tranny oil (GL4) and shifter seal question

Single & twin cylinder model BMW Airhead specific discussions
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jjwithers
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tranny oil (GL4) and shifter seal question

Post by jjwithers »

My /2, is starting to leak transmission oil from the shifter seal.
Before i dig into the repair, i figured I would check in and see if there are any tricks i'd need to know.
The parts fiche show a shim behind the shifter which sparked my curiosity.


Also, i read the BMW service notice that stated to use only GL4 oil on these old transmissions.
I'm looking for recommendations on which kind (Brand and viscosity) of 'off the shelf' oil I can get at my local auto parts store. Many say they are rated for GL4 and GL5 but i want to make sure it won't cause more harm then good.

thanks in advance.

-josh
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Kurt in S.A.
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Re: tranny oil (GL4) and shifter seal question

Post by Kurt in S.A. »

At the MOA national rally yesterday, Vech again indicated that GL5 is not good for /2 transmissions and final drives. He says he came across an old Volvo service bulletin that indicated using GL5 in the transmissions would void the warranty. The issue was high sulphur content that would damage the bronze components. Of course, Vech sells GL4. Here's his info on the website:

http://www.benchmarkworks.com/articles/ ... roil.html/

I'm a bit skeptical on this. I suspect there are varying levels of sulphur in GL5 products, so some maybe better than others. But I'm not hearing that throngs of /2 owners are parked beside the road or have indicated that their transmission was destroyed by GL5. Maybe the process takes a long time. BMW never issued any kind of service bulletin on this.

I run GL5 in my bikes.

Kurt in S.A.
Major Softie
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Re: tranny oil (GL4) and shifter seal question

Post by Major Softie »

It's a well known issue that older "yellow metals" are not compatible with GL5, and it's my understanding that it is all GL5's, not just some of them. I don't know if /2's fall into that period of sensitive metal, but I know that prewar engine lathes are NEVER supposed to have GL5 put into them (I have a 1928 Monarch AA). It would seem like a sensible precaution to avoid GL5 unless you were certain that it was alright.
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Duane Ausherman
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Re: tranny oil (GL4) and shifter seal question

Post by Duane Ausherman »

Agree with MS. Why not use GL4, as it seemed to work out OK.
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jjwithers
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Re: tranny oil (GL4) and shifter seal question

Post by jjwithers »

I ordered GL4 from Amazon of all places.

Is there anything I should be aware of when replacing the shifter seal on the transmission?
any tricks to removing or installing?
www.beemersandbits.com
'77 R100S - http://www.joshuawithers.com/r100s
'73 /5 Toaster Cafe bike http://www.joshwithers.com/slash5
'67 Bridgestone 175 Hurricane Scrambler
'66 R60/2
'72 BMW 2002
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