I was driving my 94 Prizm back home to my college house in PA and all of a sudden I heard and felt a heavy thumping. So about 200 miles into my trip (out of 435 miles) I heard/felt it. I was doing about 70-75, so I slowed down to about 50 and it was still doing it. I pulled over at the next exit and checked my cv's and there was a little bit of play (more then there should have been). So I babied it for about 50miles, doing about 50. It went away after a while. I started back up bout 100 miles later, so I said screw it and still drove bout 70 (I only had a few hours before class). I've tryed recreating the same driving conditions over the past few weeks and it has only done it a few times. But last night there was about 2 inches of snow on the ground and my tires started slipping while I was trying to get up to speed and it happened for a breif moment. I will be making the same trip back up to my normal house here at the end of March. Does anyone have the slightest idea of what the problem could be?? Thanks for taking the time to read this.