74 620 loud hum above 60mph on bumps and right turns

[Lee R]

The sound is like a wheel bearing going out but I already checked and they are fine. At around the 60mph mark and above, the hum appears with some vibration in the drivers side floor. I can also feel some vibration in the steering column and wheel. It isn't constant, just appears when there are some bumps and dips in the road or when I am making a turn to the right at these speeds. I need to replace the idler arm as there is some play in the steering wheel but I don't think this would cause the symptoms I am having. Checked all suspensions components and nothing is bent, broken, or otherwise. Bushings are pretty dried up and will be swapped with new ones when I get my idler arm. Tires and wheels in great shape. Could it be a balancing problem?

 

I know it is a little bit of a fishing exp[edition, so just looking for some insight from anyone on what I might be missing to cause this hum and vibration.

[metalmonkey47]

Tire out of balance maybe?

 

I have the same issue with my truck. I just don't go about 55mph :rofl:

[datzenmike]

Point the tires straight ahead, (have someone help you while you watch from the front) Stand 30 feet out in front and line up the front tire with thew back on one side. Now go over to the other side. Can you see the other front tire is turned out or in or is it pretty much in line with the rear? If it's turned in or out and noticeable, the toe is probably in need of adjustment.

 

Check air pressure in all tires.

 

Raise each tire and spin by hand. Is it round, or does it have a bulge in it? Does it wobble... bent rim?

 

Swap front tires to the back one at a time and try it. If the problem chances or moves the tire or rim is suspect.