Time to start prepping the car for the season and I'm going to change out the diff and trans fluids. So what kind of fluids are you guys using? I was reading through some of the stuff on Redline's website and all it did was confuse me. Here's what appear to be the choices from Redline (it doesn't have to be redline, they just seem to be the most well known):

Trans: MT-90, lightweight shockproof (but says not recommended for syncro boxes)
Diff: 75W90, lightweight or heavyweight shock proof

Jim (its66) says he ran lightweight shockproof in the trans and heavyweight shockproof in the diff and I've heard of other people using the MT-90 and 75W90.

I'm more interested in protecting the trans and diff from destruction than in transferring every last .01 hp to the ground if that makes a difference in choice.

Thanks.

David