I was checking some parts I have in my basement, I have 2 sets of gears for a 8 3/4 rear, 741 housing. One set is 3.23, but the other set come out to 3.30, which I never heard of before. Anyone ever have or use 3.30 gears ?
8 3/4 gears
- Thread starter Sterling
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It isn't stamped on the ring gear? Sounds more like a Chevy gear ratio.
Some early 8 3/4 rears used 3.31 gears. My 59 Dodge, for example.
There are part numbers stamped in, but no ratio like the 3.23 gears. 43 ring gear teeth, and 13 pinion teeth. I have never seen any for a 8 3/4 before
What are the parts numbers? They would give you a close approximation of their production dates.
To elaborate a bit, if I remember correctly, 1957 was the first year for 8 3/4 rear axles. In 59, the standard V8 rear axle ratio with Torqueflite was 2.93, with Powerflite (2 speed), it was 3.31 (to help compensate for the 1.72 low gear ratio of the Powerflite vs. the 2.45 low gear ratio of the Torqueflite).
There was also an 8 1/4 rear in this era that externally looked just like an 8 3/4, but the ring gear was smaller. Mostly for sixes I think. Don't remember what years this 8 1/4 was offered.
I think that you are correct, I brought the gears out to my garage, and looked at them closer. The pinion is marked 182865. 3.31 MS234 JWX 7. 30 57. The ring gear is 1828634. 3. 31 3117357234 HK4U. I had just never ran into a 3.31 set. Thank you for the info
Those part numbers would be late fifties or early sixties.
Interesting, will those early R&P sets fit any 741 housing?
They 3.31 gears look the same dimensions as the 3.23 gears, even the pinions both have 13 teeth. I have one 741 housing that I will try to put together and try.
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