DO NOT use light weight shock proof on the 3's tranny! It will clog the tiny lube holes in the shaft with a clay like substance that forms for impact protection. This is not recommended for synchro trannies for that reason. It is a great tranny oil and provides amazing protection just not to OUR trannies.
It's just the shock proof that is bad for our trannies. The rest of the redline products are good. The fact is that my tranny felt good with the SP but when it failed and we took it apart we found all kinds of small clay like particles in there and the holes in the shaft that are used for lubing were clogged with the clay so no oil was getting between the gears. That to me = bad news. I switched to redline MT90 or Royal purple the 2nd time and both work very good although I went back to redline and think I will keep using that since I've had no issues with it so far.
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