I have a 83 Camaro V6 5 speed.
Recently my shifter had been moving up and down when in first and second gear.
I can hear a scrape on the bottom from time to time when it bounces.
When in third gear it does not do it so intensely, also when driving slow in second and third
It does not bounce as much. Looking under the car I can't see anything hanging down.

Thanks for any advice.

-Matt

 

Probably a torn transmission mount, letting the thing lift. Try and push up on the tail of the trans, gently with a floor jack. If it's bad enough, you might even be able to see the separation from the side without jacking it up.

 

Bad idea to drive it like that?

 

Yes it is. A broken tranny mount can cause issues with the other 2 motor mounts, driveshaft and U joints. The tranny mount is pretty cheap around $20 for a rubber one and a few bucks more for the urethane ones. It is a simple and easy fix, just make sure you use jack stands when lifting your car.

Massey