I am now thinking of changing my rear end from a 3.73 to a 3.07 gear ratio. Does any body know what it will take, besides the ring and pinion gear and the money, to do this change? Any information will help! Thanks! ;-)
If you want a professional opinion: Randy's Ring & Pinion- http://www.ring-pinion.com 1-877-349-1367 Now for my opinion: Assuming you have an old truck 12-bolt rear and a 3:73 gear, you may have a 4 series carrier, which means- you will also need to change the carrier to accept gears which are "higher than 3:73. A 3 series carrier will accept gears from 3:07 to 3:73. You will need to check into this. the carrier has numbers stamped that will help you get your answer. I happen to be going through this with my 63 k-10. I have a 65 12-bolt with a 4 series carrier with a 3:73 gear that is shot. I call, order a new ring and pinion and find out that it is thicker than original and can't be used. Reason? I bought a gear for a 3 series carrier and in fact, I have a 4 series. So, I now bought another set of gears and am all set. Don't make the same mistake. I also don't want to discourage this task. Many people do it them selves, many don't want to bother. It requires a tool to measure pinion depth, and a typical magnetic base dial indicator to measure back lash. Things that you can do and do right if you take your time. Look through some prior posts, I believe someone helped me along with the pinion bearing slip-fit trick. Couple more places to check: http://www.differentials.com/install.html http://www.richmondgear.com/rpinstruction.html You can buy the video richmond puts out - step by step. I havent seen it, but am told it tells you what you need to know. my .02
