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BRAKE DRUM AND ROTOR SERVICE INFORMATION
TROUBLE-SHOOTING: BRAKE DRUM WEAR
Problem
Cause
Solution
A. Cracked Brake Drums
A1. New
NO PHOTO AVAILABLE
A1.
Mishandling
A1.
Replace brake drum
A2. Used
A2.
Heat checks connect
together and grow through
drum
A2.
Replace brake drum. Check brake
balance and brake system. See
Heavy Heat Check.
A3. Used, low mileage
NO PHOTO AVAILABLE
A3.
Improper shoe contact.
A3.
Replace brake drum. Shoes must
contact the drum at the center of the
shoe.
B. Heat Check
B1. Light
Heat check is 1.5” or less in length.
Heat check is sporadic across the braking
surface. No propagation. No crevices.
B1.
Normal condition
B1.
Does not impair brake performance.
B2. Medium
Heat check is no longer than 3” in length.
Heat check is not apparent across the entire
width of braking surface. Check is beginning
to propagate. No crevices.
B2.
Imbalanced brake system,
dragging brakes, improper
drum for application, or
driver abuse. It is caused
by constant heating and
cooling of brake surface.
B2.
Check brake balance, brake
return springs, brake adjustment,
proper brake drum for application,
and lining type within vehicle
combination. Monitor brake drum
and replace if heat checks grows
beyond 3”.