what additives I need to put on my rear diff ?

[Killa]

I cant find my old post any more, is dealer is only one carry the additives ? what brand and where I can get from part store ? Im going with valvoline 80w/90 with bottle of additives, thanks

 

[03ghoststang]

i believe so because i have asked at parts stores and they say they dont carry the friction modifer

 

[gsjohnson]

Buy the Friction Modifier from your Ford Dealer.

 

[Nightstick]

Dealer is probably the only one with the Motorcraft brand modifier. If you run Mobil 1 or the like, you won't need any modifier.

 

[fast97gt]

umm you can go 1 of 2 ways, 1. 75w140 full synthetic gear oil does not require modifier, and can be bought at any parts store 2. 80w90 with additve, and NO your not limited to where can buy modifier, the parts store does carry a different brand the name of it is trans-x. it comes in a like an oversized toothpaste tube, and i think its better than what ford sells.

 

[97speedster]

Run full synthetic with just a little Savalon and that is all it will need.

 

[Killa]

umm you can go 1 of 2 ways, 1. 75w140 full synthetic gear oil does not require modifier, and can be bought at any parts store 2. 80w90 with additve, and NO your not limited to where can buy modifier, the parts store does carry a different brand the name of it is trans-x. it comes in a like an oversized toothpaste tube, and i think its better than what ford sells.

Does any one knew how much dealer cost ? yes I did saw that trans-x 7oz " toothpaste " should I use all of it ? or just 4oz ? thanks

BTW couple month ago I change out the fluid, and use grey rtv without leak, and some people told me to use black rtv, what do you guy use ? thanks

 

[fast97gt]

Does any one knew how much dealer cost ? yes I did saw that trans-x 7oz " toothpaste " should I use all of it ? or just 4oz ? thanks

BTW couple month ago I change out the fluid, and use grey rtv without leak, and some people told me to use black rtv, what do you guy use ? thanks

use what you used last time for the rtv sealer, and as far as the additive you can use the whole 7oz wont hurt nothing, and itll also be better for the clutchs