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transmission oil??

bubbarus

Freshman Member
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Does anyone have a suggestion for a good lubricant for my 1976 B's gearbox? When I drained the fluid, I was suprised to find that it was green. What might that be?
 
Green? Who knows - use regular 20w50 engine oil, just like the engine. It should look "new" for a long time. If you're using an OD transmission stay away from all lubricant enhancers (slick 50, etc)
 
Obviously the wrong oil...you should use the same as the engine oil...20-50 Castrol fits the bill fine!

Bruce /ubbthreads/images/graemlins/cheers.gif
 
Green? Shouldn't be green! I have no idea what that was, but I know that you don't want it in there! The recommended oil for the gearbox on a 'B' should be regular 20W50 engine oil, plain and simple!
 
I use Ultra-violet leak detection in my car and the additives are always neon green. Perhaps somebody put a leak detector in with the oil to try and find a leak. I use it in my motor oil and in my coolant and there's no reason why it couldn't be used in a tranny or diff, they even make an additive for fuel systems and air conditioning. I got the kit from Eastwood. Otherwise, 20w50 is correct.
 
The last oil I saw that was green(dark green actually) was a hypoid SAE90 type. If you read the manual closely, it will say you can use this type in the gearbox as an alternative to the 20W-50.I never compared the viscosity over normal temperature ranges with this type of oil. Most people seem to use 20W-50 like their engine oil. I ended up using a synthetic in mine because I thought it might be a little better..
 
Supposedly synthetic will eventually cause problems with the OD wet-clutch arrangement - otherwise I'd think it would be better too!
 
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The last oil I saw that was green(dark green actually) was a hypoid SAE90 type. If you read the manual closely, it will say you can use this type in the gearbox as an alternative to the 20W-50.I never compared the viscosity over normal temperature ranges with this type of oil. Most people seem to use 20W-50 like their engine oil. I ended up using a synthetic in mine because I thought it might be a little better..

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Yeah, I was going to say it was gear oil. The floor under my Troy-Bilt is greenish.
 
I have been told that synthetic oil in an MGB trans can make things "too slippery" and cause the synchronizers not to work properly. Has anyone actually seen this happen?
 
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I was suprised to find that it was green. What might that be?

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It's been a long time since I dealt with the product, but B&M (famous for their shifters and automatic transmission shift kits) used to produce a transmission fluid that was blue. But Green? /ubbthreads/images/graemlins/eek.gif

20W-50 sounds right to me.

Mike /ubbthreads/images/graemlins/smile.gif
 
[ QUOTE ]
I have been told that synthetic oil in an MGB trans can make things "too slippery" and cause the synchronizers not to work properly. Has anyone actually seen this happen?

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I believe my synchros are even working better with the synthetic. It used to be (60s & 70s) I remember that adding Molykote to the gearbox of your British car was very acceptable -- I know I did it to all of mine. The other day I saw somewhere that it was still recommended.
 
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