What are the chances of my new car having a posi ? The guy i bought it from said possibly 3.08 Is it possible ? Any way to tell other than pulling the cover? It doesnt have a limited slip tag on the outside so i dont know o No:
There is a way to tell if it is a posi right off the bat. Put a jack under the axle and lift the tires off the ground. Keep the tranny in park or gear if a manual tranny. Can you rotate a tire? If so, then the other tire is rotating in the opposite direction. And that means it is a peg-leg. If you are not able to rotate, and you hear a clunking noise after rotating maybe 1 or 2 degrees, then you have a limited slip rear. Just becouse there is no limited slip tag does not mean anything. A previous owner may have changed the fluids and lost it or forgot to put it back on. Now for gears... Same preperation, but put stands under the axle and keep the tires off the ground. Put tranny in neutral, mark tire to a spot where you will remember where you started at. Also mark the drive shaft for reference of start as well. Then rotate the drive shaft and see how many times it takes to turn the wheel a rotation. To get a more accurate result, rotate the wheel more than one time, maybe 2 to 4 times. Then divide to get your ratio. This is a raw method to get an idea of what you have for gearing. It will give you an idea at least. Mike
I would follow Mikes directions that will help alot. In 72 a GS got a base rearend of 3.08 so it atleast is a 3.08 open. Does it have F41 suspension? Ususally the performance axle came with that.
thanks guys i didnt want to sound like a dummy, i know how to check for a posi but i dont have the car yet and i was hoping possibly it might just have one, or the numbers would tell me something,I guess i have to wait till i get it home. chris
If the axle is fairly clean, look at the front side of the pass. side axle tube. About 3-5" from the axle carrier will be a 3 letter code. This will indicate the original gears and if equipped with posi. Here is a pic of one from a 72 Skylark.
