GM Service Manual Online
For 1990-2009 cars only

Application

Specification

Metric

English

Front Brakes (RPO JC4)

  • Rotor Discard Thickness *

27.50 mm

1.082 in

  • Rotor Minimum Allowable Thickness After Refinish

28.0 mm

1.10 in

  • Rotor Thickness (new)

29.0 mm

1.14 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

Front Brakes (RPO's JF3/JF7)

  • Rotor Discard Thickness *

27.50 mm

1.082 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 (RPO JH1)

  • Rotor Discard Thickness *

27.50 mm

1.082 in

  • Rotor Minimum Allowable Thickness After Refinish

28.0 mm

1.10 in

  • Rotor Thickness (new)

29.0 mm

1.14 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

Front Brakes (RPO JH6)

  • Rotor Discard Thickness *

36.50 mm

1.437 in

  • Rotor Minimum Allowable Thickness After Refinish

37.0 mm

1.46 in

  • Rotor Thickness (new)

38.0 mm

1.50 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

Front Brakes (RPO JH7)

  • Rotor Discard Thickness *

36.50 mm

1.437 in

  • Rotor Minimum Allowable Thickness After Refinish

37.0 mm

1.46 in

  • Rotor Thickness (new)

38.0 mm

1.50 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 (RPO JC4)

  • Rotor Discard Thickness *

28.50 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

Rear Brakes (RPO JH1)

  • Rotor Discard Thickness *

18.50 mm

0.728 in

  • Rotor Minimum Allowable Thickness After Refinish

19.0 mm

0.748 in

  • Rotor Thickness (new)

20.0 mm

0.787 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 (RPO JH6)

  • Rotor Discard Thickness *

27.50 mm

1.082 in

  • Rotor Minimum Allowable Thickness After Refinish

28.0 mm

1.102 in

  • Rotor Thickness (new)

29.0 mm

1.141 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 (RPO 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.