I'm trying to determine the gear ratio of a '65 full-size rearend I purchased. I've cleaned it up a little, and I can see the numbers "40" stamped on the top and the bottom of the housing. Any ideas? Also, I'm pretty sure it's not a posi, because when I spin the hub, the other side spins the opposite direction. But, if I turn the pinion, both sides spin in the same direction.
Take the cover off, drain the lube, and look on the ring gear. There will be 2 numbers, divide the smaller into the bigger for the gear ratio.
This is a front loaded, drop-out style rearend. I'd prefer to not crack the thing open, since I drove the car home that it came out of, and I know it's good.
Hmm. I think I'll clean the thing up more thoroughly, to try and find some more codes/stampings. Thanks for the help.
According to my 65 manual: PB - 3.07 for Auto Trans PC - 3.42 for Manual Trans PD - Special Order PO - 3.07 Posi for Auto Trans PP - 3.42 Posi for Manual Trans PR - Special Order If it is posi there should be a 1/2" circle with an x through it on the bottom side. Ahh screw it, I'll attach a pic...
