Rear End Gear identification
 

can anyone tell me the best way to id what rear end gears I have in my truck. I'm assuming it's stock (72 Chevy Cheyenne Super) but have no idea what stock gears are. I looked under the truck today but couldn't find any numbers. Am I overlooking some type of id numbers somewhere? I am looking at upgrading to a 350 350hp 385tq and want to see if my current rear end will jive with that. Anyone have any suggestions?

Re: Rear End Gear identification
 

so theres 2 main options. either take the diff cover off, or theres a way you could jack it up and count the turns of the tire and drive shaft, but im not totally sure what that procedure is, but i bet someone would be glad to give you it!

Re: Rear End Gear identification
 

Mark the driveshaft. While turning the wheel one full revolution, count the number of times the driveshaft rotates and that's your ratio. A little over 4 driveshaft revolutions to one wheel revolution would be 4.11's.

Re: Rear End Gear identification
 

Assuming it's not posi, you have to turn the wheel 2 complete rotations and count the driveshaft revolutions.