1997 Honda Civic LX.

Brake pads and rotors have around 4,500 miles on them. Took wheels off to inspect CV boots and noticed on the passenger side the brake pads are wearing unevenly. The outside pad is wearing quite a bit more than the inside pad. I flipped the caliper up and slid it back and forth on the pin. It seems to slide freely so I don't think that is the problem.

Does anyone have any suggestions as to what could cause this issue?

Thanks!

 

Is the rotor surface where the outer pad contacts more rough and grooved than the inner rotor surface? If so, have the rotors turned or replace them as well as the pads.