how many quarts should i buy for a rear gear swap? i'm thinking of buying the Redline Synthetic 75W90...i just need to know how much (or a different weight oil if i'm picking the wrong one...)
you're gonna need about two quarts to be on the safe side and you need to stay away from the syn oil when it comes to gears. Get regular gear oil because its nice and thick. The syn oil=great for engines, not that great for gears. The best i can think of is either "Redline" or "Royal Purple" oils. They are both top notch.
You run ATF in the tranny, not the rear..
Its takes good ole 80w or so for the dif...
I swapped over to synthetic back 10k ago when i rebuilt my Trak-Loc...the oil was damn clean and still see thru, so I just filtered it and threw it right back in when it put 373s in last week...
Regular NAPA gear oil is just fine, thats what I run in mine.
FYI If you have an aftermarket differential like an EATON or AUBURN then YOU DONT want to run synthetic oil in it. Belive it or not but its not good for them. My friend chris just took out his auburn and put a rebuilt stocker back in b/c the auburn was only spinning one tire b/c it was trashed from using syntehic oil. Just a heads up........