Squeak from the tires

I have an '02 Nissan Xterra. It sounds like the front tire or tires squeak. It is a metallic “chirping”. It is most noticeable between 25 mph and 35 mph and can be heard only with the windows down. Furthermore, once the brakes are applied the squeaking stops even as the car continues to roll to a complete stop.



It has been ongoing for almost 2 years and the mechanics at the dealership cannot determine the cause (or don’t want to determine the cause). It was first only noticeable when turning to the right. While it is most prevalent when turning right, it now occurs when traveling straight or to the left.



Any suggestions to get the mechanics headed in the right direction would be most appreciated.