First a big hello to all here,and thanks in advance.I am a new member.I do not know much about cars but i am learning.I recently bought my 82 Caballero, 350/350th.How can I tell what my gear ratio is?? I know from the reciepts that came with the car that a posi unit was installed,but all of the receipts went through the washer machine!!!!!! with the info on gear ratio and posi unit etc.I looked on Drivetrain Superstores,and according to them the stock rear is a GM10 bolt 7.5 26 axle spline ,27 pinion spline ,7.625 ring gear 3.23 gear ratio.How can I definitley tell what I have in there now????? It drives great on the highway.I was looking for a little more take off power.

Welcome to ECC/NECOA!

It's either a 2.41, 2.56, 2.73, or 3.08 rear end. To see how to identify your rear gears read this:

Gear Ratio Code (http://www.geocities.com/malibunirvana/technical/rear_ends/axle_code.html)

Hey thanks a lot for the info on the codes.What if the gears have been changed already???Do I have to physically remove the differential cover to find out what gears I have????Are there numbers stamped on the ring ,and pinion gears itself????Are the ratios you mentioned the only ones that the rear I have can hold because of ring gear diameter?????Thanks ,Kraig

Since your 82 has had a 350 engine transplant, there's a good possibility that other drive train components aren't original as well. If you want to be sure, pull the cover and count the teeth. Divide the pinion teeth into the ring teeth. Numbers are stamped on the ring gear which give the number of teeth also but you still have to do the division. There are lots of different ratios available from aftermarket companys like Richmond Gear.

Great!,Thanks again for the info.This site is great.

You do not have to take the diff cover off to find out what ratio you have. Turn the rear wheel one full turn (exactly) and count how many times your driveshaft makes a full turn. However many turns the shaft makes during the 1 turn of the rear wheel, thats the gear you have in there. Ex: during one full turn of my wheel, my driveshaft made slightly over 3 full turns, wich means i have a 3.08 gear.

Thankyou again.All of this info is greatly appreciated.