08Brake Safety Tech Tips

CATALOG NUMBER 08 Did you know approximately 4 million commercial motor vehicle inspections are conducted every year throughout North America? This ensures that large trucks and buses are safely operating on our roadways. In 2023, 54,207 trucks were put out-of-service because of brake violations. Brake systems were the number 1 cause for out-of-service violations, accounting for 25% of level I and V road check inspections. BRAKE DRUMS 1. The max. allowable brake drum diameter is stamped/casted into the outer edge of the drum. 2. Place a brake drum diameter gauge inside the drum. 3. Take several measurements within 90 degrees of each other at the open and closed edges of the drum's friction surface. 4. Replace your brake drum if... » Any of these measurements are 0.12-inch. » The brake drum is out-of-round. 5. Common problems with brake drums include... » Grease Stained Drums, Cracked Drums, Heat Checking, Oversized Drums, Scored Drums, Excessive Wear and Galling, Blue Drum, Martensite Spotted Drums, and Polished Drums. SLACK ADJUSTERS 1. Verify the retaining bolt or snap ring is correctly secured in the camshaft. 2. Check slack adjuster gear torque - use a lb-in torque wrench and turn adjusting nut counterclockwise. 3. Replace your slack adjuster if... » The torque value is less than 45 lb-in as you rotate gear, slack adjuster is operating correctly. » The torque value exceeds 45 lb-in as you rotate gear.

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