7.5" diff fluid

[ZEN50]

Wondering if the 7.5" differential uses the same fluid as the 8.8? Would the 1986 Turbo coupe need the friction modifier fluid?
Would royal purple 75w 140 fluid work, ok?

[Foxy 83.5]

Wondering if the 7.5" differential uses the same fluid as the 8.8? Would the 1986 Turbo coupe need the friction modifier fluid?
Would royal purple 75w 140 fluid work, ok?

Yes to all.

[bwguardian]

The original Ford spec was 80w-90, then it was changed around 2001 to 75w-140 for the 8.8 axle. You could use the heavier weight if it's traction lock, but may be a bit much for an open differential. Most all gear oil is synthetic nowadays and also already has the friction modifier in them, so make sure if the new oil has it in there as too much friction modifier is not good.

[richpet]

What they said is accurate.