vibration in 1st gear, i don't think it's wheelhop
 

Now with the cold Chicago weather i get this vibration when i start in 1st gear. It seems to be clutch related because it only happens while i release the clutch and it only happens in 1st gear. I tried starting with 2nd and it doesn't happen. My clutch still seems to be in great shape, no slipping or anything, what could this be?

bump......