Thoroughly clean and inspect the parking brake drum for cracks, scores, deep grooves and out-of-round any time the parking drum is removed.

Slight scoring can be cleaned up with a fine emery cloth. Heavy or extensive scoring causes excessive brake lining wear. The drum braking surface will need machining to remove heavy scores.

The drum should not be machined if the drum is grooved and the brake linings are slightly worn. Instead, polish the drum braking surface with a fine emery cloth. Eliminating all of the drum grooves and ridges on the lining would require removing too much metal and lining material. The grooves and ridges match and satisfactory service can be obtained by leaving the grooves and ridges alone.

Measure the inside diameter of the brake drum at two or more places around the circumference of the braking surface. The measurements must bemade at the same distance in from the edge of the drum.

Measuring the drum for taper involves taking measurements at the inner and the outer edges of the machined surface at two or more places around the drum.