What kind of diff fluid would you guys recomend I use. Also every other fluid. I know they have the different kinds Lucas, Royal purple...ect. Im gonna change all my fluids in the truck and i wanna use the "good stuff". What do you think is the best.

 

I recomment Motorcraft for your engine, transmission, and transfer case oil. I also recommend Quaker State 75w90 Full Synthetic for your diffs.

 

Lucas and Royal Purple are really good. There is also Amsoil. I personally use Royal Purple except for in the engine.

 

Synthetics are the best. Motorcraft is a compromise between cost and quality though still better than most.

Synthetics cost more, but prevent wear better. Ones like Amsoil have longer term additive packages. I only change my oil once a year -- about 20K miles between changes and the oil tests fine. Not for everyone though, lol -- we've been programmed to not believe that's possible and some people can't overcome the fear.

I used Amsoil full synthetic in my auto tranny and when I opened it to rebuild it, it was in very good shape with almost no wear on the soft parts even at 90K miles.

Royal Purple is about as good though I'm not sure if it's for long drain or not.

 

o no John, you said AMSOIL

 

Amsoil in every thing... what else?

 

I use Amsoil in every part of the truck that takes amsoil. Thats good you change your oil every 20K. I thought Amsoil was good up to about 5K. Thats what I've been changing my oil but if I can get another 5K at least I'd be happy. Let me know more info on this..

 

I'm using mobil 1 synthetic 75W140 in my diffs with L/S additive in the rear for my L/S