Looked up the fluid... There's 2 on this unit. It's a Haldex supplied clutch pack system, almost identical to what's used in Saab, Ford, and Volvo. The fluid for the differential clutch pack, GM part #88863349, was almost $64 a quart, my price! I've seen some insanely priced fluid, but c'mon. It says right on the bottle that it's just 75w90. What could be so special about this stuff?