I have a 1992 Firebird with the 191ci motor and to my knowledge, the stock automatic transmission and rear end. It's happened before, but today was bad...

It seems like when the car has been running for a while and when I'm already in a higher gear. Mostly on the interstate, when I give it a little gas to pass someone I'll feel a huge block and it will stop accelerating, I'll hear a deep metallic sound and then it's fine and I can speed up. This doesn't always happen. It's actually sort of rare. For the past couple weeks I've had no problem and I think I had it floored at one point when pulling out so I didn't cut someone off and nothing.

Then today it was the worst, I gave it a moderate amount of gas at about 40-50mph to pass a semi in traffic and then I hear the loud bang and hear it while it stop with power and then stops. I went to hold the current speed and it did it again and shut off. I pulled over, put it in neutral and started it right up and drove home slowly. Sounds pretty major.

Thoughts? Torque converter, rear end going out? The engine is about 1 year out of a full rebuild.

 

Edit: Thanks admin/mod

 

Btw, it doesn't necessarily happen while it's shifting. It usually happens when I'm in the highest gear but has happened in 3rd.

 

Bump: Could something as simple as a rear diff fluid change help? This is a high mileage car and I couldn't tell you the last time someone changed the oil back there?

If not, maybe something in suspension?

 

Any ideas for me to try? I have to drive my car 3 1/2 hours to my campus beginning fall and back around Christmas time. I just don't want whatever it is to screw me over on the trip there or back.