Drum Brake System: Testing and Inspection

1) If the inside surface of brake drum is streaked, correct the surface. And, if it is unevenly worn, taperingly streaked, or the outside surface of brake drum is damaged, correct or replace it.





2) Measure the drum inner diameter.

Drum inner diameter: "L"
Standard: 228.6 mm (9 inch)
Service limit: 230.6 mm (9.08 inch)

3) Measure the lining thickness.

Lining thickness:
Standard: 4.1 mm (0.161 inch)
Service limit: 1.5 mm (0.059 inch)

4) If the deformation or wear of back plate, shoe, etc. are notable, replace them.
5) When the shoe return spring tension is excessively weakened, replace it, taking care to identify upper and lower springs.