GM Service Manual Online
For 1990-2009 cars only

Application

Specification

Metric

English

Front Brakes J41/JM4

  • Brake Pad Lining Minimum Thickness

1.0 mm

0.039 in

  • Brake Pad Lining Thickness - New

12.0 mm

0.472 in

  • Brake Rotor Diameter, 4 Stud J41/JM4

256.00 mm

10.079 in

  • Brake Rotor Diameter, 5 Stud JM4

280.00 mm

11.024 in

  • Brake Rotor Discard Thickness*

22.0 mm

0.87 in

  • Brake Rotor Maximum Allowable Assembled Lateral Runout

0.06 mm

0.002 in

  • Brake Rotor Maximum Allowable Scoring

1.50 mm

0.059 in

  • Brake Rotor Maximum Allowable Thickness Variation

0.025 mm

0.001 in

  • Brake Rotor Minimum Allowable Thickness After Refinish

22.75 mm

0.896 in

  • Brake Rotor Thickness - New

23.69 mm

0.933 in

Front Brakes JL9 (With LNF)

  • Brake Rotor Diameter

315.5 mm

12.421 in

  • Brake Rotor Discard Thickness*

24.0 mm

0.945 in

  • Brake Rotor Maximum Allowable Assembled Lateral Runout

0.06 mm

0.002 in

  • Brake Rotor Maximum Allowable Scoring

1.50 mm

0.059 in

  • Brake Rotor Maximum Allowable Thickness Variation

0.025 mm

0.001 in

  • Brake Rotor Minimum Allowable Thickness After Refinish

24.2 mm

0.952 in

  • Brake Rotor Thickness - New

26.0 mm

1.023 in

Front Brakes JL9 (Without LNF)

  • Brake Rotor Diameter

296.00 mm

11.653 in

  • Brake Rotor Discard Thickness*

22.8 mm

0.898 in

  • Brake Rotor Maximum Allowable Assembled Lateral Runout

0.06 mm

0.002 in

  • Brake Rotor Maximum Allowable Scoring

1.50 mm

0.059 in

  • Brake Rotor Maximum Allowable Thickness Variation

0.025 mm

0.001 in

  • Brake Rotor Minimum Allowable Thickness After Refinish

23.0 mm

0.906 in

  • Brake Rotor Thickness - New

26.0 mm

1.023 in

Rear Brakes JL9 (With LNF)

  • Brake Rotor Diameter

292.0 mm

11.496 in

  • Brake Rotor Discard Thickness*

18.0 mm

0.709 in

  • Brake Rotor Maximum Allowable Assembled Lateral Runout

0.06 mm

0.002 in

  • Brake Rotor Maximum Allowable Scoring

1.50 mm

0.059 in

  • Brake Rotor Maximum Allowable Thickness Variation

0.025 mm

0.001 in

  • Brake Rotor Minimum Allowable Thickness After Refinish

18.2 mm

0.717 in

  • Brake Rotor Thickness - New

19.9 mm

0.783 in

Rear Brakes JL9 (Without LNF)

  • Brake Rotor Diameter

270.0 mm

10.630 in

  • Brake Rotor Discard Thickness*

11.8 mm

0.465 in

  • Brake Rotor Maximum Allowable Assembled Lateral Runout

0.06 mm

0.002 in

  • Brake Rotor Maximum Allowable Scoring

1.50 mm

0.059 in

  • Brake Rotor Maximum Allowable Thickness Variation

0.025 mm

0.001 in

  • Brake Rotor Minimum Allowable Thickness After Refinish

12.0 mm

0.472 in

  • Brake Rotor Thickness - New

14.0 mm

0.551 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 specification.