I have finally decided to replace the 50 pontiac rear in my 32 chev(see album if interested). Is there any way to tell gear ratio of a rear from case numbers/stamping etc? Aware of spinning it but if that isn't practical? Am thinking of gm 10/12bolt? Coupe runs a warm 327 w/350TH. Strictly a street car for an old fart looking for ease of repair and reasonable rpms at highway speed. With the pontiac turning near 4k at 75/80. Thanx
I don't know of any code stamped on a 10 or 12 bolt rear that designates the ratio; there could have been, but on any rear with a removable cover, I never thought that it was a big deal to pull the cover and look at the gears. Either the ring gear or the end of the pinion gear will have the tooth count stamped on it---something like 43 13---and you divide it to find the ratio. 43/13=3.31. I always want to change the rear end lube anyway.
Larry,try to find a 10 bolt from a '70s Camaro Firebird or Nova,most will have a decent ratio as they were set up for that ******....ratios:3:08-3:42.[correct width] Unless it was from a SS or 4 SPEED CAR it should be one of the above ratios..... A 9" from a Galaxy in the 60's will also fit and are mostly 3:00 thru 3:50 ratios.....which would cure your hiway Hi revving problems. another rear that will fit widthwise is an S10 4x4 from 88-95,lots were sent out with 3:42 gears.... I dont know what you have for wheels//Pontiac[5 0n 5 or adapters] but will need to address that I guess....
thanx heathen and chop rods for info. i did forget to mention I have adapters on the 5x5 to run chevy 4 3/4. appreciate the reminder!
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