So to begin I drive a 1997 Trans Am, picked it up about a month ago. On the way of driving it home SES light came on so i started kickin myself in the ass for buying the car (craigslist deal) only to realize it was a bad cat. ANYWAYS new problem arose a few days ago. I took the car to my dad's and wanted to take him for a ride (he's a huge gear head) and I figured hed appreciate the car. Well on the way there I was getting on it pretty hard and all of the sudden a huge uh "Bang/Thud" hit the bottom of my floor right by where the tranny is. Freaking out I made sure it shifted through all the gears fine. I've got an automatic so i shifted through the gears manually too. Everything is fine until I put it under a load and then as soon as I do I get a big thud on the floor again. I popped the hood and showed my dad and he seems to think it's a motor mount or one of the tranny mounts.. Any suggestions? I'm puzzled, because I've been hearing several different things from different people.