So I drove to SC with my car and everything was fine, but then i got new tires up there, and on the way back to memphis, I decided to punch the gas a little in 5th gear, well right around 80mph, it started to vibrate a whole bunch, and it kinda smoothed out as i got off the gas. The thing is, this happened right after i got new tires mounted and balanced. Also from a dead stop, when i get goin specially in first and second gear, the steering wheel kinda wobles from side to side.....

anyone have any ideas?? to what it is?

 

Assuming the tires were balanced correctly, possibly a bad wheel bearing. I'd make sure the tires were balanced right first though.