Procedure for checking brake pads and rotors
1 of 2
Photo 1: Check the pad thickness
Measure the pad thickness by placing
the compass points between the backing
plate and the rotor. Measure the thickness
at both the top and the bottom of the pad.
2 of 2
Photo 2: Check the rotor's condition
Run your fingernail across the rotor
surface. If your nail catches in deep grooves,
the rotors should be machined or replaced as
Here’s how to check your brakes yourself in two steps.
First find a safe area to test your
brakes and check for brake pedal
pulsation. Brake to a stop from
about 30 mph. The pedal should
feel smooth with no pulsation at
all. Then try braking at highway
speeds. If you get pulsation, the
rotors are “warped” and must be
machined or replaced.
With the engine cold, remove a
front wheel. Then use a compass
and a tape measure to check the
brake pad thickness (Photo 1). A
new brake pad is about 1/2 in.
thick. Replace the pads when they
get down to 1/8 in. Compare the
readings top to bottom; they
shouldn’t vary by more than 1/16
in. If they do, the caliper isn’t
releasing properly and must be
serviced. Finally, check the rotor disc for grooves (Photo 2).