What are dimpled rotors?
Let's talk about dimpled rotors. Dimpled rotors are actually quite similar to the dimples on your face. No joke! The need for dimpled rotors arose because enthusiasts with heavier cars were looking for an improved rotor that had better cooling and brake pad outgassing properties than just a plain rotor.
What are dimpled rotors? Dimpled rotors are brake rotors that have a dimpled cavity. These indentations on the rotor's contact surface, round in nature, allow the brake bad to outgas properly. Its minimal depth doesn't affect the structural integrity of the rotor, thus it's also a great solution for heavier SUV's and trucks. As a matter of fact, heavier SUV's and trucks is one of the factors that stemmed the development of the dimpled rotor. The dimpled rotor is an evolution of the cross-drilled rotor designed for track and sport cars. Because SUV's and trucks exert a much higher load and stress on the brake rotors, the dimpled rotor is recommended due to the higher stress handling capacity.
Outgassing is important as it allows the brake pad to "breathe". This bit of extra breathing room is especially vital in situations of heavy load such as towing or instances of heavy brake use.
For lighter cars such as coupes and sedans, the cross-drilled rotors offer the same outgassing functions with a bit better cooling capacity.