My aunt owns a 98 Trans Am and she just had her starter replaced for the third time in two years. when she put it on she started it up. it started fine but as the car is running it is making a lot of racket from the starter/flywheel. she has used the shims in every direction to solve the problem but nothing has helped. she seems to think it is the flywheel and i somewhat agree with her but i wanted to ask you guys. oh yeah also every now and then when she went out to start her car the starter would just grind hence why she replaced the starter to begin with. like i said it starts up now without any prob other than the extremely loud clanking noise under the car.

 

It sound to me like the starter isn't disengaging properly. This can be caused by a defective bendix (the gear that moves in and out on the starter). I would take it to the part store/garage where she got the starter from so they can hear the sound it makes before she tries to have it replaced under warranty.

The intermittent grinding I dunno about...whenever I replace a starter if there's any question of flywheel damage I rotate the flywheel through 360 degrees and visually inspect every tooth. It's possible that there is one damaged area on the flywheel.

I ran across this on shbox also...

 

Yeah, for whatever reason, it sounds like the starter is either not fully disengaging, there's some damaged flywheel teeth, or maybe you need some more/different shims for the starter.