67 Chev 12 bolt differential
 

My 67 C10 currently has 3.73 rear gears, has a 250 inline 6 and 3 on the tree. Looking to change the rear gears to lower rpm at higher speed. I'm told if I go lower than 3.55 I have to change the carrier also. Anybody have any knowledge of this?

Thanks...

Re: 67 Chev 12 bolt differential
 

I'm sure someone will correct me if I'm wrong ,but sounds correct. My '67 12 bolt has 3.08 gears. I can only go up to 3.42 ratio.
I believe there are 2/3/and 4 series carriers?!

Re: 67 Chev 12 bolt differential
 

I wish you lived closer, we could just swap rear ends and save each other a boatload of money haha. There are different series of carrier, and if I remember right 3.73 is the tallest gear for its carrier but somebody will chime in that has more experience

Re: 67 Chev 12 bolt differential
 

https://www.ringpinion.com/b2c/DiffD...&DriveType=RWD
This site should give you some answers.there are a ton of these rearends out there so don't give up hope.