Hi,

I am going to look at a used 9 bolt for sale. I was told it was out of an 88 GTA (axle is already removed)

Seller did the "torque test" for me and said it took over 50 ft/lbs to turn one side with the other locked (hopefully confirming the cones are ok)

Does this test alone confirm it must be a posi?

thanks, I'm a noob with axles and I was thinking of swapping this supposed working one in while I try to do the cone repair on my worn out one.

thanks,
-Dan

Yes.

I've only seen ONE pic of ONE of that model rear that wasn't posi, so your odds are pretty good regardless.

cool thanks! now gotta hurry up and get it!

If you turn one wheel and the other turns the same way it is a posi. I think this works with the GM posi.

I've never seen or heard of an open diff 9-bolt, but as old as they are, there is no guarantee that the posi is still good inside. Most likely is, but ya never know. My 87 9-bolt is perfectly alive.