I was wondering if I could use Royal Purple Gear Oil (http://www.royalpurple.com/prodsa/mgeara.html) in my rear diff. I have a 1996 F-150 and the tags say it takes 75W140. If I use royal purple will I need to add something because it says in the web site I that I don't. Thanks!!!!

 

I just did the lube change on my 02 and added the Mag-Hytec cover. I used the Royal Purple 75W140. No, you don't need to add friction modifier as it is already in it like the web site states. I have had no problems with the Royal Purple ... a little expensive at $10.50 a quart. Hope this helps.

02 F150 Super Crew Lariat FX4 White & Silver
5.4 /w Roush Cold Air Intake & K&N filter
3.55 LS
Flowmaster Cat Back
JBA Silver Cat4ward Headers
Rancho RSX's
Rancho Steering Stablizer
Hellwig Rear Anti Sway Bar
Lightning Tails
Outland Sport Bumper Guard
Hella 550's
Silverstars
Superchips 9100 Micro Tuner c/o Troyer Performance
Underdrive Pullies c/o Troyer Performance
Mag-Hytec Trans Pan & Rear Cover

 

Amsoil Severe Gear 75W-140 would be my choice.