i have an 01 supercrew with 235,000 miles on it. most of them are highway but the rear end fluid needs to be changed. with that many miles and use oin it should i stick to the factory recommended 75W-140 or something different? the only problem i have out of it is a slight grinding noise going from a stop but only when the fluid is nice and warm and every now and then. what all should i check when changing the fluid other than metal shavings etc?

 

Royal purple 75-140! all the way!!!!

 

Do you guys change it yourself or have it done? If you do it yourself what method do you use?

 

I do it myself with the royal purple and some Permatex Red silicone "make a gasket". Just loosen all the bottom bolts, then pry with a flat head on the seal at the bottom. let the oil drain out, then take all bolts out. Make sure to get all old gasket off. I take this time to clean my cover, I even sand it down, and I painted mine red. Then put the silicone on, bolt the cover back on. then start fillin her back up. Very simple.

 

I think I'd check out the source of the noise, then make preps to drain and replace the lube....and 75W140 GL5 full synthetic is required for the Ford 8.8" axle.

 

Awesome thats what I was planning on doing. thanks!!!

 

And don't forget the friction modifier if it's a limited slip.

 

RP has the friction modifier in it!

 

I bought Royal Purple 75W-140 for mine when I did it and I asked Mike Troyer (a reputable tuner and mech) about it. The Royal Purple states it has the friction modifier in it also and he told me they use that and still add the Ford friction modifier. Just my 2 cents.

 

what should i be looking for as far as the noise goes? i dont kow much about rear ends......any advice would be great!!!!