WARNING: This page is about a different car, the 2008 GMC Sierra, 2008 GMC Cab & Chassis Sierra, 2008 Chevrolet Silverado, and 2008 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

Application	Specification
Application	Metric	English
Front Brakes JF3, JF7
Rotor Discard Thickness*	28.0 mm	1.10 in
Rotor Minimum Allowable Thickness After Refinish	28.0 mm	1.10 in
Rotor Thickness (new)	30.0 mm	1.181 in
Rotor Maximum Allowable Lateral Runout	0.05 mm	0.002 in
Rotor Maximum Allowable Scoring	1.50 mm	0.059 in
Rotor Maximum Allowable Thickness Variation	0.025 mm	0.001 in
Front Brakes JD9, JH6, JH7
Rotor Discard Thickness*	36.50 mm	1.437 in
Rotor Minimum Allowable Thickness After Refinish	37.0 mm	1.457 in
Rotor Thickness (new)	38.0 mm	1.496 in
Rotor Maximum Allowable Lateral Runout	0.13 mm	0.005 in
Rotor Maximum Allowable Scoring	1.50 mm	0.059 in
Rotor Maximum Allowable Thickness Variation	0.025 mm	0.001 in
Rear Brakes JD9
Rotor Discard Thickness*	18.0 mm	0.709 in
Rotor Minimum Allowable Thickness After Refinish	18.5 mm	0.7282 in
Rotor Thickness (new)	20.0 mm	0.787 in
Rotor Maximum Allowable Lateral Runout	0.25 mm	0.010 in
Rotor Maximum Allowable Scoring	1.50 mm	0.059 in
Rotor Maximum Allowable Thickness Variation	0.009 mm	0.0004 in
Rear Brakes JH6
Rotor Discard Thickness*	27.5 mm	1.083 in
Rotor Minimum Allowable Thickness After Refinish	28.0 mm	1.102 in
Rotor Thickness (new)	30.0 mm	1.181 in
Rotor Maximum Allowable Lateral Runout	0.13 mm	0.005 in
Rotor Maximum Allowable Scoring	1.50 mm	0.059 in
Rotor Maximum Allowable Thickness Variation	0.025 mm	0.001 in
Rear Brakes JH7
Rotor Discard Thickness*	28.5 mm	1.122 in
Rotor Minimum Allowable Thickness After Refinish	29.0 mm	1.142 in
Rotor Thickness (new)	30.0 mm	1.181 in
Rotor Maximum Allowable Lateral Runout	0.13 mm	0.005 in
Rotor Maximum Allowable Scoring	1.50 mm	0.059 in
Rotor Maximum Allowable Thickness Variation	0.025 mm	0.001 in
* All brake rotors have a discard dimension cast into them. Replace any rotor that does not meet this specification. After refinishing the rotor, replace any rotor that does not meet the minimum thickness specifications.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Disc Brake Component Specifications

Use the Manual With the Right Hardware

When to See a Mechanic

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