Doomah

Looking for a set of 3.73 gears for my rear end, I have a 1970 type O POSI rear with 3.23 gear in it and a 671 carrier, I would need the carrier and gears for 3.73.

Thank You

oldsmobiledave

No such animal. Choose 3.42 or 3.91 as those are your choices. Used or NOS as no one is making new ones.

Doomah

I thought if I change the carrier in the unit i would be able to get 3.73 or will no other carrier fit in my rear end?

Magna86

With a 71 and up fear you can get that ratio. O type you get 2.56, 2.78, 3.08, 3.23, 3.42, 3.91, 4.33, 4.66, and rare 5.00. The aftermarket carrier used in our rear still only use the O type gears. Want 3.73 find a 71 and up corporate rear core and get it rebuilt. Parts are cheaper generally than O type.

orange442

Richmond gears makes 3.42 and 3.90 gears that are a direct fit for your current posi unit. There has never been a 3.73 gear made to fit the O type 12 bolt. If you are set on getting 3.73 gear, get an 8.5 10 bolt out of a 71-72 Cutlass or Skylark and then you can buy just about anything to build it as there are many different posi units and lockers for 8.5's as well as many manufacturers that make gears for it.

Doomah

Thank you for the replys

67442nut

3.73 gears are only in the 12-bolt Chevy rear ends like come in the Canadian built Oldmobiles.