CarsDirect.com explains that when a vehicle shakes as it slows down and the brakes are applied, worn brake rotors or unevenly worn pads are likely culprits. According to the source, excessive wear on the rotors and the amounts of heat generated during braking alter the shape of the rotor turning a normally flat surface into one with smalls peaks and valleys.
Another possible cause of shuddering or vibration while braking is brake pads that are unevenly worn. This is due to the brake pads failing to make complete, steady contact with the rotors.
AGCO Automotive Corporation suggests that warped rotors or unevenly worn brake pads indicate deeper problems with a vehicle's braking system. Three common root causes of these conditions are extreme driving styles and excessive braking, using brake pad materials that are incompatible with the vehicle's rotors and brake calipers that are binding. If one or more of these root causes is present, replacement rotors and brake pads may also experience abnormal wear.
CarsDirect.com gives tips on how drivers can check the health of their brake pads and rotors easily. Most vehicle wheels allow the owner to see through to both of these important components. Brake pads should wear evenly and have ample pad material left, while healthy rotors are free of grooves, surface checks, cracks and contaminants.