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OK Dumb Diff Questions


Full Member
Jan 26, 2005
Grant, MN (aka Stillwater, MN)
Ok I have a 2003 1500 Z71 (G80 Locker) I know all Z71s are 1500s but I'm just providing as much info as possible.

What size Diffs Front and Rear would be in this. I am getting ready to tackle a fairly good sized project. Or actualy a couple projects. I have to pull the rear end appart to replace both backing plates. I'm due for the 100,000 mile fluid change anyhow. Then I will be replacing a output shaft seal on the front Diff. Again I'm due for the fluid change so I might as well do it all now. Also on the subject as long as I'm doing this should I replace the other output shaft seal as long as I have the diff drained? The driver's side has failed and who know how much longer the passenger side will last.

I know the diffs are sized in inches but I haven't seen anything translating RPO codes to say what size diffs I have. While I guess I don't have to know it would be easier as I could then figure out how much fluid to have and such.