Brake Rotor

Description

Heat checking is a common occurrence on brake rotors, particularly those that are frequently exposed to high temperatures, such as during aggressive driving or on a race track. The rapid heating and cooling cycles cause the metal to expand and contract repeatedly, leading to these tiny cracks on the rotor’s friction surface.

• Is it a problem? For a regular street car, a small amount of heat checking is usually not a cause for immediate alarm, but it is a sign that the rotors have been subjected to high heat. However, if the cracks are deep, long, or extend all the way to the edge of the rotor, it can be a safety issue and the rotor should be replaced immediately. In some cases, a mechanic might be able to resurface the rotor to remove the cracks, but only if the rotor is still above its minimum thickness specification.
• What causes it?
  • Excessive Heat: The primary cause is repeated exposure to high temperatures from heavy or frequent braking.
  • Driving Habits: Aggressive driving, such as “riding the brakes” on a long downhill descent or repeated hard braking, can generate enough heat to cause this.
  • Brake Pad Issues: In some cases, low-quality brake pads that don’t dissipate heat well can contribute to the problem.