The car runs smooth between 0-50 mph. When it reaches 50mph, it starts to vibrate. But when it crosses 60mph, it becomes smooth again.. I'm not sure what the problem is??

 

Could be due to wheel balance, tire rotation issues, uneven tire tread, wheel bearing failure Torque converter problems and so on. Has the vehicle ever been in an accident? When was the last time you got new tires or had them balanced and rotated?

 

I bought the car about 2 weeks ago. i just got the wheel alignment done... I guess the wheels are not too bad...They would last for this summer.... This car has got a clean title....

 

How did the car drive before the wheel alignment?

Also did you do a tire rotation or tire balance?

 

It's sorta common for wheel balancing problems to occur in a range of speeds, but OK at slower speeds.

 

a bad alignment will not make the car shake at hwy speeds ,a bad alignment will cause a pull or uneven tire wear ,,, most likely you got tires out of balance, bent rims, worn suspension parts, I would have the wheels balanced first ,,

look in the DIy section there is a write up on this

 

I had the same problem, at the same speeds.

My issue was solved by having the tires balanced.

 

Alignment can and will cause your car to vibrate. Poor alignment will slowly but surly cause funky wear on your tires and could create choppy tread. I agree that worn suspension parts. Perhaps the sway bar bushings are worn. I've recently changed mine due to a considerable amount of road noise in the cabin and some vibration traveling through from the in need of replacement tires. The job was very easy and improved the ride a great deal, plus, it stopped that 'clunk' I heard when I would hit the slightest crack or whatever in the road.

 

if the car wasn't reported during the accident it won't show up on the records, title, carfax, insurance and so on

 

let me say it again,, an out of specs alignment WILL NOT cause a car to shake at hwy speed or any speeds,, It will cause tire wear ( which in turn can cause noise or possibly a shake depending on how worn they are ) or create a pull,, thus it is not an out of specs alignment but bad tires ......you can have an out of specs alignment with good tires and not feel any vibration at all