1972 C10 4X4 Rear Axle Ratio


Supporting Member 1
I have a 72 heavy half ton with posi rear end & need to find the gear ratio without opening . The RPO is G8O. I've searched the web and get numerous hits but none of them let me know the ratio.

Where else can I look for this info?


The listing says C10 and it should be K10. My bad.


Well Known Member
Supporting Member 9
Since it is a posi, you could jack up both wheels, turn wheels one turn and count the turns of the drive shaft. I like to start with the valve stem down, mark the drive shaft, and turn the wheel one turn until the valve stem is back at the bottom.


I'd do what Ron said. And may I also add I'm jealous! I always get the darn peg leg rears! :bang

Looking for some posi's for my trucks if you know of any. One is a 12 bolt in my 69 stepside, would love to find a 3.55 for it and the other is an Eaton H072 or H052 in my 71 C20. Need a 4.10 for that one. :deal There, I got a free wanted ad in. :D
I dont know if you are still looking for the eaton. no posi's that I have ever seen. Only detroit nospins I have 4 with complete 3rd members 4.10 and 4.56. if you want let me know. BC