hey guys, i recently changed the rear diff fluid on my 00L. it was changed about 7000 miles ago but i had to change both rear axel seals two weekends ago so obviously i needed new fluid. i put in royal purple 75 140 synthetic fluid that said i didnt need any friciton additives. i did not put in a friciton additive and it has been driving fine. should i still look into putting that additive or am i fine with what i put in????

385rwhp/476tq

 

You're good. A FM is not required when using RP.

 

ok good thanks alot

 

Amsoil was saying the same thing but drive it a few days and go into a parking lot and do some figure 8s. If you hear some chatter, put half the quantity of FM specified by Ford. It did the trick for me. This is a case that more is not better so use as little as possible. The Ford FM will work with any fluids.

 

ok def will do i think im guna add a little just to be safe rather than sorry. thanks for the help guys