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Disc Brake Specifications

DISC BRAKE ROTOR SPECIFICATIONS

Application (1) Disc Diameter - In. (mm) Original Thickness - In. (mm) Minimum Refinish Thickness - In. (mm) Discard Thickness - In. (mm) Rear Brakes Brake Assist
Gasoline
C Series (Light Duty Only)
JB1 11.86 (301.2) 1.04 (26.4) 0.980 (24.9) 0.965 (24.5) 11 X 2 Inch Drum Manual
JB3 11.86 (301.2) 1.04 (26.4) 0.980 (24.9) 0.965 (24.5) 11 X 2 Inch Drum Single Diaphragm Vacuum
G Series (Light Duty Only)
JB1 11.86 (301.2) 1.29 (32.7) 1.23 (31.2) 1.22 (31.0) 11 X 2 Inch Drum Manual
JB3 11.86 (301.2) 1.29 (32.7) 1.23 (31.2) 1.22 (31.0) 11 X 2 Inch Drum Single Diaphragm Vacuum
C & G Series (Except Light Duty), K & P Series
JB5 11.86 (301.2) 1.29 (32.7) 1.23 (31.2) 1.22 (31.0) 11.15 X 2.75 Inch Drum Dual Diaphragm Vacuum
JB6 12.50 (318.0) 1.28 (32.5) 1.23 (31.2) 1.22 (31.0) 11.15 X 2.75 Inch Drum Dual Diaphragm Vacuum
JB7 12.50 (318.0) 1.28 (32.5) 1.23 (31.2) 1.22 (31.0) 13 X 2.50 Inch Drum Dual Diaphragm Vacuum
JB8 12.50 (318.0) 1.54 (39.1) 1.48 (37.6) 1.47 (37.3) 13 X 3.50 Inch Drum Hydro-Boost
JF9 14.25 1.54 (39.1) 1.48 (37.6) 1.47 (37.3) (2) 13.75 X 1.54 Inch Disc Hydro-Boost
Diesel
All Models
JD3 11.86 (301.2) 1.29 (32.7) 1.23 (31.2) 1.22 (31.0) 11 X 2 Inch Drum Hydro-Boost
JD5 11.86 (301.2) 1.29 (32.7) 1.23 (31.2) 1.22 (31.0) 11.15 X 2.75 Inch Drum Hydro-Boost
JD6 12.50 (318.0) 1.28 (32.5) 1.23 (31.2) 1.22 (31.0) 11.15 X 2.75 Inch Drum Hydro-Boost
JD7 12.50 (318.0) 1.28 (32.5) 1.23 (31.2) 1.22 (31.0) 13 X 2.5 Inch Drum Hydro-Boost
(1) Lateral runout for all rotors is 0.004" (0.01 mm). Parallelism for all rotors is 0.0005" (0.013 mm)
(2) The Original thickness, minimum thickness, discard thickness, lateral runout and parallelism specifications are the same for both rear 13.75" and front 14.25" diameter rotors.