Chevrolet Silverado / GMC Sierra. Service manual — part 2366

BRAKES SELF APPLY WHEN TURNING STEERING WHEEL

booster?

Go to Step 4

Go to Step 6

4

1. Disconnect the vacuum check valve from

the booster to relieve vacuum reserve.

2. Separate the master cylinder from the

vacuum brake booster. Do not disconnect
any brake pipes.

3. Inspect the rear of the master cylinder for a

brake fluid leak.

4. Inspect for brake fluid in the vacuum brake

booster.

Did you find a brake fluid leak?

Go to Step 5

Go to Diagnostic
Starting Point -
Hydraulic
Brakes

5

Replace the brake master cylinder and the
vacuum brake booster.
Did you complete the replacement?

Go to Step 8

-

6

1. Wipe clean the external surface of the

master cylinder to hydraulic brake booster
area, if equipped.

2. Separate the master cylinder from the

hydraulic brake booster, if equipped. Do
not disconnect any brake pipes.

3. Inspect the rear of the master cylinder for a

brake fluid leak.

Did you find a brake fluid leak?

Go to Step 7

Go to Diagnostic
Starting Point -
Hydraulic
Brakes

7

Replace the brake master cylinder.
Did you complete the replacement?

Go to Step 8

-

8

1. Install or connect components that were

removed or disconnected during diagnosis.

2. Road test the vehicle to confirm proper

operation. Refer to Brake System Vehicle
Road Test.

Is the condition still present?

Go to Step 2

System OK

2008 Chevrolet Silverado 1500

2008 BRAKES Hydraulic Brakes - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

DISC BRAKE SYSTEM DIAGNOSIS

Test Description

The numbers below refer to the step numbers on the diagnostic table:

9: Lubricant leaks from non-brake system components may come in contact with and
contaminate brake system components.

10: Lubricant leaks from non-brake system components may come in contact with and
contaminate brake system components.

12: Disc brake rotor shields/backing plates that come in contact with disc brake rotors may
cause brake system noise.

15: Disc brake rotor thickness variation that exceeds the maximum acceptable level can
cause brake pulsation.

19: Disc brake rotor thickness variation that exceeds the maximum acceptable level can
cause brake pulsation.

22: Disc brake rotor assembled lateral runout (LRO) that exceeds the maximum acceptable
level can lead to thickness variation.

Step

Action

Yes

No

1

Were you sent here from the Hydraulic Brake
Symptom table?

Go to Step 2

Go to Diagnostic
Starting Point -
Hydraulic
Brakes

2

Inspect the brake assist system for proper
operation. Refer to Brake Assist System
Diagnosis (Hydraulic Assist).
Did you find and correct a condition?

Go to Step 4

Go to Step 3

3

Inspect the steering system for proper operation.
Refer to Diagnostic Starting Point - Power
Steering System (w/o Electro-Hydraulic
Steering) .
Did you find and correct a condition?

Go to Step 4

Go to Diagnostic
Starting Point -
Hydraulic
Brakes

4

Road test the vehicle in order to confirm proper
operation. Refer to Brake System Vehicle
Road Test.
Is the condition still present?

Go to Step 2

System OK

2008 Chevrolet Silverado 1500

2008 BRAKES Hydraulic Brakes - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

Step

Action

Yes

No

DEFINITION: This diagnostic table is designed to diagnose ONLY the components of the
DISC brake system in order to determine if the DISC 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 Diagnostic
Starting Point -
Hydraulic
Brakes

2

Visually inspect the disc brake pads for the
following conditions:
Refer to Brake Pad Inspection .

Lining thickness below specifications

Uneven and/or abnormal wear - edge-to-
edge and/or side-to-side

Looseness or damage - including pad
hardware

Evidence of contamination from an
external substance

Did you find any conditions to indicate a
concern with any of the front and/or rear disc
brake pads?

Go to Step 3

Go to Step 12

3

Are any of the front and/or rear disc brake pads
contaminated?

Go to Step 8

Go to Step 4

4

Are any of the front and/or rear disc brake pads
worn unevenly?

Go to Step 7

Go to Step 5

5

Are any of the front and/or rear disc brake pads
and/or pad hardware loose or damaged?

Go to Step 7

Go to Step 6

6

1. Remove and inspect the worn disc brake

pads for glazing, looseness, heat spots or
damage.

2. Replace the worn disc brake pads as a

complete axle set. Refer to Front Disc
Brake Pads Replacement (JH6, JH7)
or Front Disc Brake Pads Replacement

-

2008 Chevrolet Silverado 1500

2008 BRAKES Hydraulic Brakes - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

(JD9, JF3, JF7) and/or Rear Disc Brake
Pads Replacement (JH6, JH7) or Rear
Disc Brake Pads Replacement (JD9) .

Did you complete the inspection and
replacement?

Go to Step 12

1. Remove the front and/or rear disc brake

calipers, as appropriate, from the
mounting brackets and support the
calipers. Refer to Front Brake Caliper
Replacement (JH6, JH7) or Front
Brake Caliper Replacement (JD9, JF3,
JF7) and/or Rear Brake Caliper
Replacement (JH6, JH7) or Rear
Brake Caliper Replacement (JD9) .

2. Inspect the disc brake caliper mounting

bracket and the mounting/sliding
hardware for the following conditions:

Refer to Front Disc Brake Mounting
and Hardware Inspection and/or Rear
Disc Brake Mounting and Hardware
Inspection .

Binding or seized hardware

Worn, damaged or missing hardware

NOTE:

Support the brake caliper with heavy
mechanic wire, or equivalent, whenever it is
separated from its mount and the hydraulic
flexible brake hose is still connected. Failure
to support the caliper in this manner will
cause the flexible brake hose to bear the
weight of the caliper, which may cause
damage to the brake hose and in turn may
cause a brake fluid leak.

IMPORTANT:

Do NOT disconnect the hydraulic brake flex
hoses from the calipers.

2008 Chevrolet Silverado 1500

2008 BRAKES Hydraulic Brakes - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado