ImolaRocket

The gearbox and the front diff share fluid. So I want to open both the gearbox drain and the front diff drain plug, and then fill both through the gearbox fill plug....correct? They combined take a little less than 3 liters? I plan on using RedLine MT-90 75w90 synthetic because it is rated GL-4 for the synchros? But the rear diff I just use 75w90 synth gear lube, and that can be GL-5 in the rear?

LaserK04

Use MT90 in the gearbox, and redline 75W90 GL-5 in the rear diff.

Blown Nogaro

Or you can just use Amsoil 2000 series 75W-90 gear oil for both tranny and rear differential.

ImolaRocket

Also, open both drain plugs in the front?

Blown Nogaro

Yes. I've heard some people use them with good results. In fact, I have 5 quarts in my desk.