Dealing with this issue in my cousin's 67 Firebird with a stroker 400. It now has wiped the thrust bearing twice. First time blamed the pressure in the tranny as the tranny had been rebuilt. This was a new build with the new stroker crank - old stock crank was fine.

In 125 street miles lost 0.010 inches in the thrust with the rebuilt motor. We are trying to cover all bases this time.

We want to know for sure if the tranny is causing excessive thrust on the crank so I believe we will measure the thrust force on the crank before we tear it apart. We have a plan...........