Hello can anyone tell me if my 72 Riviera has a C-clip or non C-clip rear end and if the axle is configured like the attached diagram?
IN 1971-1976 Gm implemented a cubic inch to size rear rule of thumb... Normally if the car had a 455 you got the 9 3/8 Oldsmobile rear if the cars had 400 350 they could get hte 8.875 pontiac reaR. (pONTIAC REAR HAD A 10 BOLT SCALLOPED COVER WITH 12 BOLT RING GEAR AND LARGE 1.875 PINION SHAFT. tHE oLDS REAR HAD 12 BOLT COVER AND 12 BOLT RING WITH 1.875 PINION SHAFT DIAMETER. BOTH these rears were Bolt In Axles and both were 31 spline 45 degree cut axle spline angle. The older 1965-1970 GM axle spline full size car 31 spline axles were old 60 degree spline more straight up and down looking. YOU CAN NOT fit the newer axle spline in the older posi BUT you can fit the older axle spline in the newer 45 degree spline posi / open side gear. Just some good useful info for down the road... JIm J D RAce
Not super sure but this is how I think it goes... Some with a manual please correct if necessary 2.28 2.41 2.56 2 series 2.73 2.93 3.08 3 series 3.23 3.42 3.73 and beyond 4 series this rear has come with 3.90 4.33 ratios also from the factory We have had 2 sets of 4.33 ratios in hand at one time in the past. Original GM stuff Jim J D
Hate to high jack this thread, but I will do it anyway. What are the carrier breaks on a 9 3/8 corporate, also what is a posi unit out of a 9 3/8 worth? Out of a 72 Riv with 2.93 gears. I have the whole rear end but there is a little bit of rust on the pinion, everything else seems excellent. Thanks
3.08 would be good, but no one makes gear sets for the 9 3/8" Buick rear. That means you need to find them 2nd hand. That will not be easy.
There is no BUICK rear in 1972.... that is a OLDS 9 3/8" rear...Buick lost all rears in 1970. Only Pontiac Olds and GM 8.5 were available. in 1971 for the FULL size cars.
Might as well just use a 10 bolt 8.5 rear same deal and it bolts right in. 1971-1976 10 bolt 8.5 rear is a direct bolt in from any FULL size GM car. riv Electra Catalina Bonneville 98 88 olds etc. Look for the LOW HP motor cars. 350 2 bbl 400 etc. Centurion Chevys Impala Caprice etc should have the 8.5
Hey there .. your Riviera came with the 9 3/8 oldsmobile differental under it .. side note if anyone has 3:42 gears for this style of rear id be interested in them
Attached is the axle housing tube end flange dimensions. Made drawing when transplanting '76-'78 Seville rear disc setup onto my '71 Riviera years back.
Humm... Must have remachined the holes then huh... cause 76-78 seville is a small axle tube end the 71 Riv is a full size car flange pattern you have up. Here is the Seville measurements.