Let me know if any of you all know what is going on.

1. Oil pressure... Usually stays between 30-60 psi. Every once in a while while the car is warming up it is around 15-20 psi.... Normal or strange?

2. I replaced the carrier bearing the other day because of the well known vibration it causes. It fixed the problem, but I noticed shifting into 4th and 5th I get kinda a hard slam in the rear. I haven't checked the motor mounts yet, I will be doing that Monday. I find it strange that it only happens in 4th and 5th. Now, when the car is cold, I get the carrier vibration again. But only in early morning / late night when it is cold out.

All you Z guru's out there. let me know what you think.

 

Oil pressure is fine. The sending unit is known to be troublesome. As long as it shows pressure, you're generally fine.

Regarding the clunking, could be u-joints or a bushing... inspect everything in the rear subframe.