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MG MGB GT V8 Factory Originals Technical - Proper Fluid for GM T5 Transmission

Trying to confirm the proper lubricant for a GM T5 transmission = is Dextron III correct? 5.9 pints?
Don Faber

I ran my Borg Warner T5 on Dexron III for over 250 000 miles and no problems.

Not sure of the amount but the Borg Warner used the "little finger in the filler hole" method.
HTH, Cheers, Pete.
Peter Thomas

Don, not sure about the GM T5s, but the Ford units used different lubes depending on if they were world class or not. I believe Ford switched over to world class in 86. Hope this helps!

G.P. Copes

E-mail Red Line for their recommendation for synthetic lube. This is what I have always used in T-5's & T-50's. Sorry I don't have any on hand to get you a number, it is all at the shop.

Jim Stuart

If you are going to email somebody then why not email GM?

Peter Thomas

For those unaware...
After '86 the T-5's were redesigned as "World Class" 5 speeds and started using ATF for oil.

I see the Dextron as the obvious choice as the ford ATF has frictional fact, it used to be and still is an old racers trick to use the ford ATF in the GM automatics for a harder shift.

This same component may (?) have some adverse effect on the longevity of a standard transmission's gears..although insignificant, for this reason alone I see the Dextron as being the safe choice.

anyone have a confirmation on this?

Not sure about the effects on the gears themselves but there are some concerns about the Ford ATF reacting negatively with the material used in the sycroniser rings in the GM T5's.


Peter Thomas

This thread was discussed between 23/02/2004 and 27/02/2004

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