One day I am driving home, and the highway in front of me is completely empty, so I decide to step on it just for fun. I go through ever gear perfectly, until I reach 4th gear. I shift into 4th at about 57-5800 rpms, just like I do for every other gear, but when I release the clutch, my car shakes violently and goes "bam bam bam". It feels like the rear end was extremely shocked. I push the clutch back in as fast as possible, and am scared to death. I slow down, and go through all my gears. Everything feels fine, even 4th feels normal. So I figured, maybe I did something stupid and didn't get 4th in all the way, so it shocked the rear and tried to pop out of gear.
I didn't get on it like that for quite a while, because it scared me, but tonight on my way home, a GT pulls up next to me wanting to go. I figure what the heck, I have been dying for a race. We go from about 55 or so. Again everything is fine, but when I shift into 4th it does the same thing again, and this time I made sure it was in 4th. The car shakes, it makes the banging noises, and I notice that my low traction light comes on. I push the clutch in quickly, and then release it. It still shakes and so on... So I slow down, and come to a stop at a light. The guy wants to go again from a stop. I think, okay, I'll go, and see if it does that dang thing again. This time when I shift to 4th, I shift at 5000 instead of right below redline. It shifts fine. No shaking or banging. I have no idea what is going on. It only shakes and bangs when I shift at redline, and only in 4th gear. To me it feels like the tires locked up or something. Sorry this is so long, but I wanted to be thorough. Please Help!!! Does anyone know what is going on?
Oh, I forgot to mention that I just recently put in a B&M Ripper 2-Piece Short Shifter. Never did it before the short shifter.

 

and you positive you shifted into 4th and didn't miss shift or something?

 

You could try a easy way and put the stock shifter back in and then try it. I dont think it is the shifter but its a easy way of eliminating it.

 

Yeah, I'm sure. When I was racing the guy I slowed my shift into 4th down a bit so I could make sure that I got it in. When it did that crap, I pushed in the clutch and pulled back on the stick seeing if it wasn't in gear, but it didn't go back into the gear any more.

 

sounds like u went to 2nd instead

 

I didn't go into 2nd. I know it was 4th gear.

 

that would be my guess