Drum Brake System: Testing and Inspection

Fig. 3 Measuring Brake Drum Inside Diameter:

1. Measure brake drum inside diameter. Inside diameter should be 7.87 inches, Fig. 2.

Fig. 4 Measuring Brake Shoe Lining Thickness:

2. Measure brake shoe lining thickness, Fig. 3. Minimum thickness should be 0.040 inch.
3. Inspect brake lining and drum for proper contact and replace drum or shoes as necessary.
4. Inspect wheel cylinder for corrosion or damage.
5. Inspect backing plate for wear or damage.
6. Inspect bellcrank components for bending, wear or damage.
7. Apply a suitable lubricant to backing plate contact areas.