Bowdy04

Just want to make sure...if i use Royal Purple gear lube I don't have to add ford racing friction modifier right?? and should i get the install kit? I have an 04 with only 3K on it.

devinsteen

YES, you need to add some kind of additive when you change the diff. fluid.

cammedlx

yeah you will have to get the friction modifier and i would still get the install kit but you really don't need it but you mine as well do it right the first time

deesgt

Is this always or just when you use synthetic diff fluid because it's so slippery?

cammedlx

you always have to put a bottle of friction modifier in when changeing the fluid because of our trak loks

GiddiupStang

I recently changed out my diff fluid(full synthetic) and did not add any type of friction modifier. What will happen If I do nothing about this? I plan to make a 2 hour trip on tomorrow...

97 GT 5spd with original 2.73 gears.

cammedlx

well you trak lok in your rearend will not function properly you will just do a one wheel peel and after while it will burn out your trak lok

Bowdy04

Giddiup...you'll be fine...if you used a synthetic with it already added..what u add?...Redline and Royal Purple both already have the friction modifier added in the gear oil...i checked it at their site....only need to add the modifier if the oil added doesn't have it.

cammedlx

really??? you learn something new everday

vfast

yep..should save it on the label...take a look