Can anyone tell me the capacity of the rear diffenential on a 2004 Chevy
2500HD 2wd (Duramax, Allison, 3.73 gears)? Also, what type/weight of lube to use - I presume it's 75w-90 but the owner's manual doesn't list anything for the differential. The housing looks pretty big, like it might take a gallon or so (plus additive because it's a locking rear end), but I'd like to know before I get into it.
Thanks in advance - Jonathan