Just a quick question I have a 1980 GMC Jimmy 4X4 with a non-dana 10 bolt front, 12 bolt corporate rear, TH350 tranny, NP205 transfer. I recently as every few months pulled my diff. covers and changed the gear oil but I forgot to check the ring gear in it again. Does anyone know if these had standard ring gear and could tell me what it is? I hoping for 3.73 and not 3.10 but any help would be thankfull.


:skull:

Could be anywhere from 3.01 - 4.10, I believe. Only way to tell is to jack it off the ground and count the rotations with the tranny in neutral. (Assuming you don't want to open up the difs again.)

J. J.

pull the diffs. and eliminate the guesswork......:p :p

You don't need to pull the difs, just the covers. :p :p

J. J.

If your lucky the spec sheet in the glove box will list the gear ratio. My 89 lists the 3.73 that it came from the factory with.