markd

I have a 2004 GS300 with almost 8K miles and recently noticed excessive noise (high pitched hum) that appears to be coming from the tires. It is very annoying between 25-50 mph. The tires are inflated properly at 32 psi and I believe that this started happening recently. Has anyone else had this experience? Any solutions?

Lexusfreak

Try rotating them & make sure they are properly balanced. Do you know if your Michelins are 'directional' tires or conventional 'uni-directional'?

Brandon@TR

The 225/55 16 HX MXM is symetrical and non directional. I'm guessing this is what you have.

markd

I took the car into the dealer yesterday. The service guy took a ride with me and acknowleged the noise. His guess was that the tires are wearing unevenly thus causing the noise. Of course, this is completely a guess as he had never experienced this before. His suggestion was to roatate the tires and see if that helps. The tires a non-directional, in other words it does not matter which way they turn.

The tires were rotated and there is not a substantial difference in the noise level. The pitch of the hum may be slightly different but it is still there. I want to put a few more miles on the tires to 'even out' the wear before I reach a conclusion. Not real happy.

Lexusfreak

Are the tires balanced correctly? A rotation may not help much if they are out of balance.

markd

When the dealer rotated the tires, it was not mentioned whether the tires were balanced, probably not. I can say that there is no vibration, etc. at any speed, in fact, the car is unbelievably smooth. The noise still exists as a high pitched hum especially at around 45 mph. Spoke with my contact at the dealer briefly and we have not yet determined the next step.