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Problem
Cause
Solution
B. Heat Check (continued)
B3. Heavy
Heat check in excess of 3” in length.
High frequency of propagated heat check.
Crevices appear in braking surface cracks.
B3.
Imbalanced brake system,
dragging brakes, improper
drum for application, or
driver abuse. It is caused
by constant heating and
cooling of brake surface.
B3.
Replace brake drum. Check brake
balance, brake return springs, brake
adjustment, proper brake drum for
application, and lining type within
vehicle combination.
NOTICE: These classifications are made based on the worst area of the brake drum that is affected by heat check. It does not
need to be visible completely around the braking surface.
For example: If a drum has localized heavy heat check in an area that is approximately 6” across but the rest of the drum has no
apparent heat check, the classification of this drum would be HEAVY.
C. Grooving
C1. Fine Grooving
C1.
Abrasive material or poor
quality brake lining.
C1.
Rebore brake drum within normal
limits or replace the drum and lining.
See (A2) Turning the Brake Surface.
C2. Grooves along edges of lining
C2.
Grooves are usually
caused by foreign material
between the drum and
lining. Deep grooves can
cause a localized section of
the drum braking surface to
be worn beyond the wear
out limit.
C2.
Replace brake drum if beyond worn
out limit.
C3. Grooves coincide with rivet holes
NO PHOTO AVAILABLE
C3.
Loose rivets, bolts or
foreign material collecting
in rivet holes.
C3.
Replace brake drum if worn beyond
worn out limit.
BRAKE DRUM AND ROTOR SERVICE INFORMATION
TROUBLE-SHOOTING: BRAKE DRUM WEAR