I have a 98 Mustang with rear disc brakes. I just changed the rear disc pads and rotor on the driver side. I put everything back together and took it for a ride around the block. The brakes are working well but when I returned to the drive way the rotor is discolored and the brake pad is smoking. What is going on?

 

A bit of smoke after installing new brakes is not abnormal. The oils from assembly and a fresh pad will smoke after the heat gets to them. Discolouration after a short drive, may mean you assembled it incorrectly.