1987 mustang unknown vibration

Hi My names is James Miller,

I have an 1987 ford mustang with a 2.3 L engine. The problem is when the car reaches between 55 ? 60 mph it starts to vibrate severely in the drivers seat as well as in the steering wheel, but when it reaches between 70 ? 80 mph the vibrations go away. The first thing I thought of was that the rear wheel bearing where getting really bad and the vibrations were traveling, so I looked up troubleshooting the bearings and found that if bearings are getting bad the tire shaft from the differential there should be a little play when forced up-down-left-right, but when I tried, it was as tight as the book said it should be.

So I was wondering what you guys would suggest to be the next step in the troubleshooting process?

how’s your tires?

Alignment and tire balance could be the problem.

yes I had the tires checked and they were also fine. thank you for the quick response!

How were the tires checked? It sounds like a broken belt to me. That can sound just like a rough bearing. The car will have to be jacked up and the tires rotated slowly to see if there is any “wobble” to the tread.

I rotated the tires and the vibration didn’t change, but when I let out on the clutch the noise also stays the same.

You may want to check the wear on the tie rods.

I just replaced the tie rod ends, ball joints, struts, and brakes and calipers.