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Chevrolet Silverado / GMC Sierra. Manual - part 2369
DRUM BRAKE SYSTEM DIAGNOSIS
Test Description
The number below refers to the step number on the diagnostic table:
18: Drum brake backing plates that come in contact with brake drums may cause brake
system noise.
Step
Action
Yes
No
DEFINITION: This diagnostic table is designed to diagnose ONLY the components of the
DRUM brake system in order to determine if the DRUM brake system is operating
properly. You will be directed by the appropriate Symptom table to go to other brake
system diagnostic tables as appropriate.
1
Were you sent here from a Brake Symptom
table?
Go to Step 2
Go to
2
1. Remove the brake drums. Refer to Brake
Drum Replacement .
2. Inspect the drum brake shoes for the
following conditions:
Lining thickness below specifications
Uneven and/or abnormal wear - edge-
to-edge and/or side-to-side
Contamination from an external
substance
Looseness, damage, glazing, or
incorrect lining material
Did you find any conditions to indicate a
concern with any of the drum brake shoes?
Go to Step 3
Go to Step 7
3
Are any of the brake shoes contaminated?
Go to Step 4
Go to Step 5
4
1. Inspect the wheel cylinders for evidence of
an external brake fluid leak.
2. Replace any wheel cylinder that is found to
be leaking brake fluid. Refer to Wheel
Cylinder Replacement .
Did you complete the inspection and
-
2008 Chevrolet Silverado 1500
2008 BRAKES Hydraulic Brakes - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado
replacement?
Go to Step 6
5
1. Inspect the drum brake hardware for any
components which are worn, damaged,
discolored due to stress, broken or missing.
Refer to Drum Brake Adjusting
Hardware Inspection .
2. Replace components as required. Refer to
Brake Shoe Replacement .
3. Replace the drum brake shoes. Refer to
Brake Shoe Replacement .
Did you complete the inspection and
replacement?
Go to Step 8
-
6
1. Clean the remaining drum brake system
components to remove any traces of the
contaminant.
2. Inspect the drum brake hardware for any
components which are worn, damaged,
discolored due to stress, broken or missing.
Refer to Drum Brake Adjusting
Hardware Inspection .
3. Replace the drum brake hardware
components as required. Refer to Brake
Shoe Replacement .
4. Replace the contaminated brake shoes.
Refer to Brake Shoe Replacement .
Did you complete the cleaning, inspection and
replacement?
Go to Step 8
-
7
1. Inspect the drum brake hardware for any
components which are worn, damaged,
discolored due to stress, broken or missing.
Refer to Drum Brake Adjusting
Hardware Inspection .
2. Replace components as required. Refer to
Brake Shoe Replacement .
-
2008 Chevrolet Silverado 1500
2008 BRAKES Hydraulic Brakes - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado
Did you complete the inspection and, if
necessary, the replacement?
Go to Step 8
8
1. Check the diameter of each of the brake
drums.
2. Make a determination for each brake drum
if the drum can be REFINISHED and
REMAIN ABOVE the minimum
requirements.
Refer to Brake Drum Diameter
Measurement .Does the brake drum meet the
minimum requirements for REFINISHING?
IMPORTANT:
Make the following determination AND
ANSWER the question INDIVIDUALLY for
EACH drum.
Go to Step 9
Go to Step 11
9
1. Inspect each of the brake drums for the
following surface and wear conditions:
Refer to Brake Drum Surface and Wear
Inspection .
Braking Surface Conditions
Heavy rust and/or pitting
Cracks and/or heat spots
Excessive blueing discoloration
Missing balance weights
Braking Surface Wear Conditions
Deep or excessive scoring
beyond maximum acceptable
level
Radial runout beyond maximum
acceptable level
IMPORTANT:
Make the following determination AND
2008 Chevrolet Silverado 1500
2008 BRAKES Hydraulic Brakes - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado
2. Make a determination for each brake drum
if the drum requires refinishing based upon
the results of the inspection.
If the brake drum exhibits any of the
following conditions, it requires
refinishing.
Drum exhibits one or more of the
Braking Surface Conditions listed
previously
Drum is beyond the acceptable level
in one or more of the Braking Surface
Wear Conditions listed previously
Does the brake drum require REFINISHING?
ANSWER the question INDIVIDUALLY for
EACH drum.
Go to Step 10
Go to Step 14
10
1. Refinish the brake drum. Refer to Brake
Drum Refinishing .
2. Inspect the brake drum diameter. Refer to
Brake Drum Diameter Measurement .
Were you able to REFINISH the brake drum
within the minimum requirements?
Go to Step 14
Go to Step 13
11
Is the brake drum at or below the DISCARD
requirements?
Go to Step 13
Go to Step 12
1. Inspect each of the brake drums for the
following surface and wear conditions:
Refer to Brake Drum Surface and Wear
Inspection .
Braking Surface Conditions
Heavy rust and/or pitting
Cracks and/or heat spots
Excessive blueing discoloration
2008 Chevrolet Silverado 1500
2008 BRAKES Hydraulic Brakes - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado
Content .. 2367 2368 2369 2370 ..