I have been looking for information about how to identify the rear gearing on my 70 Electra. The only info I found was for 71+ and consists of 3 letters. I know the gearing is tall (2.73 possibly), but can't find any way to identify the rear end.
Take off the rear cover. You need to change the fluid anyway. The code for the gear ratio is imprinted on the ring gear. You will need another gasket and if it is a posi the GM posi additive. My bet is a 2.78 ratio unless you think it feels like a 2.56.
Well since it is an Elecrta...it will not be a 2.78 It will have the Buick 9.3 rear it was a BUICK ONLY REAR. so 2.56 2.73 2.93 3.07 3.23 3.42 that is it. In 1971-1976 they went to corporate set-up... eliminating the Buick rear end from the line up. all low power Full Size (FS) cars got the 10 bolt 8.5 all mid powered v8 350 400 received the 8.75 Pontiac rear (10 bolt cover 12 botl ring) kind of looks like a big tempest rear cover 455 cars got the Oldsmobile FS 12 bolt rear (12 bolt round cover with 12 bolt ring gear) Wagons also received this rear. Jim J D
That's my bet too. My '67 Electra had the 2.78:1 gearset as standard equipment while my '67 Wildcat had 3.07:1 as standard equipment. Devon
