Rear Tires Suddenly Lock Up Going 65

I find a situation involving brake pressure difficult to believe.

In order to cause this, you would have had to just about "dynamite" the brakes to cause that much pressure. Even a fairly hard stop would not cause this, and you would have remembered that at the time.

This SURELY has to be a mechanical problem in the axle or trans.

If you have a limited slip (sure grip) I could see where a brake mechanical hardware problem to be viable.

YOU NEED to tear into this and find the problem.