K 2500 Truck 4WD V8-6.5L DSL Turbo VIN S (1998)
Brake Drum: Testing and Inspection
Brake Drum Inspection (Drum Inspecting)
Any time you remove the brake drums, thoroughly clean and inspect them for cracks, scores, deep grooves and out-of-round.
SURFACE FINISH
Slight scoring can be cleaned up with a fine emery cloth. Heavy or extensive scoring causes lining wear. The drum braking surface will need
machining to remove these scores.
If the drum is grooved, and the linings are slightly worn, the drum should not be machined. 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 them alone.
INSIDE DIAMETER CHECK
Measure the inside diameter of the brake drum at two or more places around the circumference of the braking surface. The measurements must be
made at the same distance in from the edge of the drum. Compare the results with the wear specifications in Unit Repair at the end of this section.
TAPER CHECK
Measuring a drum for taper involves taking measurements at the inner and outer edges of the machined surface at two or more places around the drum.
These measurements should be equal.
BRAKE SHOE INSPECTION
Inspect the linings every 9,650 km (6,000 mi) and any time the wheels are removed (tire rotation, etc.). Inspect the shoe and lining assemblies for
wear by removing the brake drum. Replace shoe and lining assemblies when the thickness of any lining is worn to within 0.76 mm (0.030 inch) of the
shoe. Replace riveted shoe and lining assemblies when the lining is worn to within 0.76 mm (0.030 inch) of any rivet head. Always replace shoe and
lining assemblies as a complete axle set.
