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BRAKE DRUM AND ROTOR SERVICE INFORMATION
TROUBLE-SHOOTING: COMMON BRAKE DRUM
HANDLING/INSTALLATION CONCERNS
The majority of brake drums returned for warranty consideration are returned with complaints
of cracks in the mounting flange or “out of round”; however, these two conditions are commonly
caused during handling and installation of brake drums and NOT due to material/workmanship
issues. Below is a summarized list of probable causes for both types of claims.
Symptoms of drum mounting issues:
A)
Localized heat checking, blue/hard spots
B)
Vibration/shudder
C)
Loose wheels
D)
Indentations in mounting pilot on drum
E)
Crack(s) from pilot to mounting bolt hole(s) (see pictures below)
Typical Crack on Mounting Flange of Brake Drums
Reasons for cracked brake drums:
A)
Mating surfaces not clean
1.
Debris in hub pilot radius
2.
Debris on drum/hub mounting
flange surface
3.
Galvanic corrosion in aluminum
hub pilot radius (see page 85)
B)
Improper installation
1.
Drum not centered on hub pilots
2.
Drum allowed to slip off hub pilot
(see picture)
C)
Drum being installed on hub with incorrect pilot diameter
D)
Incorrect storage and/or handling
1.
Dropped or roughly handled brake drum
2.
Storing drum on its side
Common Brake Drum Handling/Installation Concerns
The majority of brake drums returned for warranty consideration are returned with
complaints of cracks in the mounting flange or “out of round”; however, these two conditions
are commonly caused during handling and installation of brake drums a NOT du to
material/workmanship issues. Below is summarized list of probable causes for b th types
of claims.
Symptoms of drum mounting is ues:
A)
Localized heat checking, blue/hard sp t
B)
Vibration/shudder
C)
Loose wheels
D)
Indentatio s in mou ting pilot on drum
E)
Crack(s) from pilot to mounting bolt hole(s) (see pictures below)
Typical Crack on
ti lange of Brake Drums
Reasons for cracked brake drums:
A)
Mating surfaces not clean
1.
Debris in hub pilot radius
2.
Debris on drum/hub
mounting flange surface
3.
Galvanic corrosion in aluminum
hub pilot radius (see pg. 85)
B)
Improper installation
1.
Drum not centered on hub pilots
2.
Drum allowed to slip off
hub pilot (see picture)
C)
Drum being installed on hub with incorrect pilot diameter
D)
Incorrect storage and or handling
1.
Dropped or roughly handled brake drum
2.
Storing drum on it’s side
Common Brake Drum Handling/Installation Concerns
The majority of brake drums returned for warranty consideration are returned with
complaints of cracks in the mounting flange or “out of round”; however, these two conditions
are commonly caused during handling and installation of brake drums and NOT due to
material/workmanship issues. Below is a summarized list of probable causes for both types
of claims.
Symptoms of drum mounting issues:
A)
Localized heat checking, blue/hard spots
B)
Vibration/shudder
C)
Loose wheels
D)
Indentations in mounting pilot on drum
E)
Crack(s) from pilot to mounting bolt hole(s) (see pictures below)
Typical Crack on Mounting Flange of Brake Drums
Reasons for cracked brake drums:
A)
Mating surfaces not clean
1.
Debris in hub pilot radius
2.
Debris on drum/hub
mo nting flange surface
3.
Galvanic corrosion in al inum
hub pilot radius (see pg. 85)
B)
Improper installation
1.
Drum not centered on hub pilots
2.
Drum allowed to slip off
hub pilot (see picture)
C)
Drum being installed on hub with incorrect pilot diameter
D)
Incorrect storage and or handling
1.
Dropped or roughly handled brake drum
2.
Storing drum on it’s side