68oldsguy

Looking for some info on changing out my rear gears in my 68 cutlass s,
12 bolt rear with 3:08 gears .Went to the local parts store and ordered a set
of 3:73 from Quality gears part # GM 12 373c rec#1759-1043 ,didn't seem to be a problem now reading some of the threads here I am doughting that these are going to work ,given that I did not read these were even a option as far as ratio ? any input would be appreciated before I rip my ride apart .Thanks

boese1978

better search some threads here before the Uber Olds Guys get after you!

1969w3155

www.supercarsunlimited Give 'em a call, they only do Olds. A couple members here are well versed on Olds rears, so maybe they will chime in.

Chesrown 67 OAI

507Olds or Monzaz on here can give you all the help and info you need. Ist off you gotta determine WHICH housing you have before you can attempt to purchase a gearset for it! send either Brian (507 Olds) or Jim (Monzaz) a PM and help will be on its way!!!

monzaz

12 bolt olds rear has bolt in axles (28 and 31 spline), Chevy has c-clip axles (30 spline). Olds 12 bolt rear has only 10 bolt ring gear- Chevy has 12 bolt cover 12 bolt ring gear.

68oldsguy

Thanks for the info and pics ,more digging required on my end ,will be back with more info

68oldsguy

I have done some digging and found the letters and numbers on the passenger side axel tube RC 08 8k or possibly a R but the diff cover looks like the true 12 bolt chev in your pictures .I tried to attach pics but was unable to (newbie) thanks again for any help?