ive got a 2002 f150 4.6 2wd and shes got about 128,000 miles on her, and i pulled the diff plug the other day and WHOA it was black and really low.

i was thinkin about pullin the cover off and cleaning it all out, im sure theres a bunch of shavings in there, and cleaning out all the burnt gear oil out of there since theres no drain plug on it, then sealing it up again and puttin it back on and putting royal purple gear oil in there,

is this gonna be to much trouble, should i just use our little vaccum (i work at a quick lube) and then put the royal purple in there and risk it mixing with the burnt oil? or will i be better off takin it apart and givin her a good cleanin

btw its the 3.55 open rear end

 

dude, this isn't that hard, trust me. the hardest part is prying the cover off, and that isn't even that bad. just unbolt it, take a scraper (I used metal) and carefully pry around to break the oem gasket sealant loose. don't use a screwdriver, pry blade, you'll risk gouging the cover. once you have the cover off, drain all the oil, and reach in w/ a rag and clean under/around the gears.

clean the cover mating surface/and the diff housing very meticulously of all gasket remnants. you want to be as thorough as possible here in order for the cover to seal properly. apply blue permatex, or a gasket and sealant and close the cover back up and bolt it down. unplug the plug, and clean it. use a transfer pump to siphon fluid in the plug hole. i'm not sure on the ford spec for the 8.8, look it up. ford specifies fully synthetic fluid ONLY. you don't need the friction modifier in an open diff. this isn't that hard, do it properly and drain/clean the rear pumpkin.

 

alright man thanks for the help!