today i got a flat tire. luckily it lasted long enough for me to get to the shop. i knew i needed an alignment but now that i got two new tires in the front the car shakes bad when i go between 60-80. is it the alignment or prolly cuz the tires werent balanced? i bought the tires used but they looked pretty darn good. the car never shook with the old tires. give me help.

 

Shaking = balancing or lack thereof. Or nasty flat spots on the surface of the tire.

If the car doesnt want to go in a straight line on a flat surface, then you have an allignment problem. Bad allignment will also wear out your tires really fast, which will show within weeks.

 

check the back tires for "humps" through out the tire. If there is, than you need to replace the back two also.

 

if it vibrates in the front of the car, like the steering wheel, thenits usually balance/bent wheel, or tire hop

 

What you just described is the wheel balancing. Flat spots in tires are typically a seperated belt (unless you locked em up). A seperated belt will be felt at ALL speeds.