Mine would move over bumps when the bolts for the shifter came loose. Check the bolts, that could be all it is.

 

Did you ever figure out what it was?

 

In terms of the shifter moving around over road bumps, ya it was loose like u said. I installed Steeda Poly Urethane bushings and it stiffened everything up and now it doesn't move one bit.

But the thing im still worried about is, sometimes, under hard acceleration (which I dont do very often) it will grind in the 1-2 shift. This has happened probly about 8 times. Do you guys think my syncros are F***ed?

 

This is acutally common with 2005 models, It probably would have grinded on you instead of your buddy if you were driving. I had this happen to my car to. also a 05, I ended up having to get a new transmission installed to fix the problem... Sorry your having to go threw this but it only gets worse. U can shift into the gear fine under normal driving but any type of "fun" driving you will not shift into the gear smoothly.