12 bolt Rear axle ratio?

[SkippyDan]

I have a 82 chevy k10 with the 6.2 diesel and i recently replaced the rear seals and bearrings and I was kinda dumb and thought I was looking at the right numbers for the axle ratio when I was in the pumpkin but after everything was buttoned up i found out i didnt have the right one. On the label that came with the truck and the specs it says i have a GQ1 - Rear Axle Standard but i have seen that it means it could be a few different ratios. I have pictures of just about every other number i could find in the pumpkin and outside. Is there a way i can tell what i have from them or not? I have read a bunch about it but i know theres a way to do it by lifting up the one side and turning the wheel but i also saw that it is not always right. Thanks in advance for the help!

 

[Strick]

Most are 3.07 ratio. Count the ring & pinion & then divide to see your ratio...which will be 3.07.

 

[Edelbrock]

Mark the U-joint (or what the U-joint bolts to), and mark axle, near where the seal is. Then mark a spot on the wheel, and a spot on the leaf spring. So that you can tell how many times each one spins. If its an open diff, you spin the wheel two times. If its a posi, you spin the wheel once. On mine, the drive shaft spun just over 4 times, when the wheel spun twice. So I have a 4:10. Had the drive shaft spun about 3&3/4 rotations for 2 wheel spins than I would have had a 3.73. About 4.5 spins would be 4.56 ratio. Pulling the cover and counting teeth works too, but spinning the wheel is easier.

 

[Ricko1966]

Dammit,read first,process second,think,then post. Ill leave my mistakes here. Sorry.
There are normally markings on the axle tubes that tell the ratio when new,Ill get you location and decode info,BIAB,I'm assuming it's a 10 bolt,which most common ratio is 3.08 12 bolt 3.07 Or you can put a mark at 6 o'clock position on one tire,as above,mark the drive shaft,push the truck forward slowly,checking the mark on the drive shaft when the mark on your tire is at 6,8,10,12,2,4 back to 6. Count drive shaft revolutions. Kind of a pain in the ass,but no more than getting out a jack and jackstands,jacking up the truck and pulling the cover or spinning the wheel.
See if you can get a code off the axle tube,post it. I'll try to identify it.