Ok, so me and a buddy lowered the front of my car last night. It was driving fine then, but when i went to go to school this morning there seems to be a very bad vibration on the left front side. The vibration goes away whenever I press the brakes and you can only feel it when i'm doing about 40+ mph. Also, it seems that if i press the gas the vibration goes away a little bit more. Any ideas??

 

have you checked anything?
sounds like your lugs are loose, but i'd like to think you would've checked that before posting.