Cracked, Scored, or Grooved Drum

NOTICE: Be careful not to drop the brake drum during handling. An out-of-round condition can occur from even the smallest fall, which may result in brake pulsation.

A cracked drum is unsafe and must be replaced. Do not attempt to weld a cracked drum.

Smooth up any slight scores. Heavy or extensive scoring will cause excessive brake lining wear and it may be necessary to refinish the drum braking surface.

If the brake linings are slightly worn (but still reusable) and the drum is grooved, polish the drum with fine emery cloth but do not refinish. Eliminating all the grooves in the drum and smoothing the ridges on lining would require the removal of too much
metal and lining, while if left alone, the groove and ridges match and satisfactory service can be obtained.

If brake linings are to be replaced, refinish an excessively grooved drum. A grooved drum, if used with new lining, will wear the lining and make it difficult to obtain proper brake performance.