Just blew 1st gear last weekend at the track (how the hell do you blow FIRST gear? I mean, 3rd, ok, but 1st? Anybody ever heard of this happening? Damn), and I'm wondering what kind of oil I should use for a tranny that sees a lot of torque and a lot of abuse. I have a 1995 VLSD (Canadian version, or I30 in the US) mated to the 3.5.

I've been using Amsoil GL-4 Synthetic and while I like it, it sometimes won't go into gear (conveniently when I'm bracket racing trying to be consistant). It feels quite lightweight, and I heard of Redline heavy shock proof oil, but this is a daily driver (except winter) so I'm not sure. With the short shifter it feels notchier than it used to so I'm looking for something to improve smoothness/shifter feel as well as some torque protection...

I read this in a SR20 forum:

"For a car that see's track use, use only redline shockproof heavy. Even a mild bolt on motor will nuke the tranny under track conditions. The transmission sees quite high temperatures when a LSD diff is installed, either quaffe or Nismo clutch type and regular gear oil turns into salad oil.

The shockproof must be changed every 40 hours of track use or so. You will lose up to 6 whp but your mean time between failure will be tripled. Depending on how you drive, failures maybe be postponed indefinatly with shockproof.

For track use you should run 15/50 synth because the SR sees sump temps of 300 plus degrees with no cooler even under mild conditions.

The difference between a lite bodied gear oil and engine oil vs the thick stuff needed for track use is around 4-6 whp of viscous drag. It is worth it though to stay away from repair bills.

Street cars with mild engine upgrades probably don't need this sort of fluids. It is manditory for track conditions."

So the heavier stuff actually makes you lose some power?