My buddy has a 1999 Chevy Cavalier. It is a 4 speed automatic. He likes to pretend it is a 4 speed Manual. So he throws it into 1 gear and then he does burnouts and stuff like that in it. He will then let off the gas pedal shift to 2 gear and slam on the throttle. It shifts and does fine. Well one day I had spent the night over there and he wanted to get something to eat. We went out to the car and started it up and he put it into Reverse and it shifted really hard. Now every time we drive his car the transmission shifts hard and bogs down. What is the problem? And is it Good to do that to your automatic transmission?

The automatic transmission on that Cavailer was not made for that type of abuse, as is now evident in the problems you describe.

Some high performance auto transmissions are designed to be used and shifted manually, but the 99 Cav is not one of them.

It is not good for the transmission.

Definitely not a good thing to do. After he pays to get it fixed, he will likely change his ways.

The problem is that your friend wrecked his tranny because he watched "Fast & Furious" too many times. There is no reason you should be "slamming the throttle" - automatic or manual. That's just abuse and no car in the world can hold up against that forever. Hopefully he'll be more careful next time around.