[] There seems to be a fair amount of internet discussion on the possible link between negative camber on Mazda 3 wheels and what is known as tire cupping. I have experienced severe cupping on the OE Toyo tires at 21,000 miles on a Mazda 3 and am reluctant to get a premium tire to try to override the problem. Tire rotation was first response to the situation, after dealer suggested that tires might benefit from rotation, but stated further that the tires were nearly at the end of their useful lives in any event (which surprised me as I have never gotten such minimal use from a new tire). A trip to the alignment shop came next, resulting in a minor alignment to the rear wheel. None of this decreased the loud tire noise. Some internet comments indicate that a "camber kit" is the only solution to this phenomenon. Any consensus on this issue?

 

The Mazda3 does have negative camber in the rear by design (that's partially how you get 0.87g skidpad readings in an economy car), this causes the tires to wear on the inside edge. Tire rotation is the only real solution without affecting your handling.

Typically a camber kit is used where someone has lowered the car and put the camber even more negative. (Mine went from -1 to -2.1 with a minor drop) I installed the Mazdaspeed camber kit and was right back at -1)

With regular rotation I got 42,000 miles out of Toyo Proxes FZ4's before I needed to replace them going into winter