I have a new set of gears in a 12 bolt that I picked up and based on the tooth count, it is a 3-series 3.90. It has Richmond gears in it stamped RICHMOND 82-0426-1 N 8620 stamped on the ring gear. I will be pulling them to replace with 3.42's. I can't seem to get any real info on the true identity of these gears. Any experts have any ideas? Thanks.
I don't have any answer for you, but I had a set of richmond gears that were a very odd ratio for a GM 8.5" rear. 3.70 by the tooth count math (not 3.73, etc). Ran the part numbers through the internet and never found a match for the gears I had on hand. Found a close number that richmond listed as 3.70, but never found an exact match. The gears ran good and quiet though.
Just call Richmond tech they will tell you exactly what you have and what carrier it is for. Jim I do all the time... Call them, that is... If your tooth count is 10 and 39 then you have 3.90 gears What carrier are you using? 30140 3 series or the 80174 4 series
