Well, recently i've gotten a new tire up front because it ran flat and could not be repaired. I wont have the money for another week to match the old front passenger with new front driver side tire. The "old" tire is not old literally, just has slightly less tread than the newer tire. When i brake, the steering wheel vibrates a decent amount. Would this be caused by the non matching tire treads on the front or my brakes?

thanks

 

Could be when you put the new wheel/tire on the bolts were not torqued properly.... no reason the brakes would go just by changing a tire

Or it could be unbalanced....

 

could be many things. unbalanced, uneven, loose lug nuts, over-tightened lug nuts. one thing i noticed is that most people tighten the **** out of their lug nuts. it shouldn't take much effort with a lug wrench to get to 100 ft/lbs. overtightening can cause the rotors to warp.

 

Its not the abs coming on is it ?
The different tire diameters could be causing it to come on if its happening just as your slowing down.
Abs compares tire rotation speed and might sense the older tire as losing traction.
If its donig it while you braking at a fast clip they most likely over tourqed your whell lugs and also unevenly and warped your rotor.
Try loosening and retorqueing them to 100 ft/lbs in the proper pattern ,might fix it .