[71chevylowrider]

I think maybe Cooters hit it on the head, a series 4 carrier starts at 3.73 & goes up, a series 3 starts at 3.07 & can go up to a 3.73, but.....I think you have to do/buy something to make it accept a 3.73, I know EFIblazer knows his stuff on these (I learned alot of what I know from talking with him) so hopefully he can shed slome light on what's nesseasary to make a series 3 carrier accept a 3.73 ring/pinion