vibration

[Richard Mordecki]

I have a 71 Mustang coupe. It has a vibration that starts after about 15 minutes of driving at hiway speeds and will vibrate for about 10 minutes then will smooth out and be fine. I have had front end aligned all wheels balanced. One thought was flat spot on tires. I bought it recently from someone who did not drive it much. Car only has 38,000 miles. Any ideas?

 

[Kit Sullivan]

It could be flat spots on old tires. Once warmed up, the imbalance fades until next cool-down period. It has happened to me on several vehicles.

 

[123FRANK321]

I've been having the same problem. Checking out my drivetrain this week.

 

[Doug The Dog]

Hi Richard! Welcome to the site! what speeds does this occur at? Does it only do it while the car is warming up, or does it come back on and off? You might check your harmonic balancer, see if it is cracked and coming apart. Do you have access to a tire company that can "road force" balance your tires? That will tell you right away if the tires are flat spotted. Good luck!

-Travis