GM Service Manual Online
For 1990-2009 cars only

Front Brake Rotor Specifications

Brake System

Normal Size O.D. x Thickness

Original Thickness

Minimum after Refinishing

Replacement (Discard)

JC5 - Vacuum

304.7x29.0 mm (12.00x1.14 in)

29.0 mm (1.142 in)

28.00 mm (1.102 in)

27.50 mm (1.083 In)

JH6 - Hydraulic

325.0x38.0 mm (12.80x1.50 in)

38.00 mm (1.496 in)

37.00 mm (1.457 in)

36.50 mm (1.437 in)

Rear Brake Rotor Specifications

Brake System

Rear Axle Ring Gear Size

Normal Size O.D. x Thickness

Original Thickness

Minimum after Refinishing

Replacement (Discard)

JC5 - Vacuum

8.6 inch

325.0 x 20.0 mm (12.80x.787 in)

20.00 mm (.787 in)

19.00 mm (.748 in)

18.50 mm (.728 in)

JH 6 - Hydraulic

9.5 inch

330.0x29.0 mm (13.00x1.142 in)

29.00 mm (1.142 in)

28.00 mm (1.102 in)

27.50 mm (1.083 in)

JH6 - Hydraulic

10.5 inch

330.0x29.0 mm (13.00x1.142 in)

29.00 mm (1.142 in)

28.00 mm (1.102 in)

27.50 mm (1.083 in)