Vettrocious

I have two C2 differentials sitting around. One has a 3.7 gear, one has 4.11

It's my understanding that the there are two types housings, one can take 3.7 and higher (i.e. 4.11, 4.56 etc) one can take a 3.7 gear and lower ( i.e. 3.5 , 3.23, 3.08) but not a 4.11. I'm trying to determine if the the one I have with the 3.7 now is the one that can take a 3.5.

Does anyone know how to (excuse the expression) differentiate between the two types?

Thanks,

Mike

redvetracr

it`s not the housing thats different it`s the posi carrier itself, one is thick one is thin on the surface where the ring gear bolts on

midstyle

Just did a quick measure; the 3-series case flange thickness (between machined surfaces) is 0.315", and the 4-series is 0.450".

I believe there is an aftermarket spacer ring that allows a 3-series to accept a 4-series ring gear.