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Disc Brake Specifications

NOTE: For additional information on S & T Series rear disc brakes, see REAR DISC BRAKES - S & T SERIES article.
DISC BRAKE SPECIFICATIONS

Application In. (mm)
Lateral Runout (All Models) .004 (.10)
Parallelism (All Models) .0005 (.013)
Original Thickness
Astro & Safari
2WD 1.04 (26.4)
AWD 1.25 (31.75)
Silhouette, Trans Sport & Venture 1.26 (32.0)
"S" & "T" Series
Front - JM3 (Brake Booster: 260 MM, Tandem High Flow) 1.03 (26.2)
Front - JC-1 (Brake: Vac. Power, 4 Whl Disc, 5500 Lbs.) 1.14 (29)
Rear - JC1 (Brake: Vac. Power, 4 Whl Disc, 5500 Lbs.) .787 (20)
All Others
11.57" Rotor ("C" & "K" Series) 1.25 (31.8)
11.86" Rotor (Express, G-Van & Savana) 1.29 (32.8)
12.50" Rotor ("C" & "K" Series) 1.26 (32.0)
12.50" Rotor (Express, G-Van, Savana & "P" Series) 1.28 (32.5)
12.50" Rotor ("C" & "K" Series) 1.50 (38.1)
12.50" Rotor (Express, G-Van, Savana & "P" Series) 1.54 (39.1)
13.75" Rotor ("C", "K" & "P" Series) 1.54 (39.1)
14.25" Rotor ("C" & "K" Series) 1.54 (39.1)
Minimum Refinish Thickness (1)
Astro, Safari
2WD .980 (24.89)
AWD 1.230 (31.25)
Silhouette, Trans Sport & Venture 1.224 (31.08)
"S" & "T" Series
Front - JM3 (Brake Booster: 260 MM, Tandem High Flow) .980 (24.89)
Front - JC-1 (Brake: Vac. Power, 4 Whl Disc, 5500 Lbs.) 1.10 (28)
Rear - JC1 (Brake: Vac. Power, 4 Whl Disc, 5500 Lbs.) .748 (1920)
All Others
11.57 X 1.25" Rotor ("C" & "K" Series) 1.230 (31.24)
11.86 X 1.29" Rotor (Express, G-Van & Savana) 1.230 (31.24)
12.50 X 1.26" Rotor ("C" & "K" Series) 1.230 (31.24)
12.50 X 1.28" Rotor (Express, G-Van, Savana & "P" Series) 1.230 (31.24)
12.50 X 1.50" Rotor ("C" & "K" Series) 1.480 (37.59)
12.50 X 1.54" Rotor (Express, G-Van, Savana & "P" Series) 1.480 (37.59)
13.75 X 1.54" Rotor ("C", "K" & "P" Series) 1.480 (37.59)
14.25 X 1.54" Rotor ("C" & "K" Series) 1.480 (37.59)
Discard Thickness
Astro, Safari
2WD .965 (24.51)
AWD 1.215 (30.86)
Silhouette, Trans Sport & Venture 1.209 (30.7)
  "S" & "T" Series
Front - JM3 (Brake Booster: 260 MM, Tandem High Flow) .965 (24.51)
Front - JC-1 (Brake: Vac. Power, 4 Whl Disc, 5500 Lbs.) 1.08 (27.5)
Rear - JC1 (Brake: Vac. Power, 4 Whl Disc, 5500 Lbs.) .728 (18.5)
All Others
11.57 X 1.25" Rotor ("C" & "K" Series) 1.215 (30.86)
11.86 X 1.29" Rotor (Express, G-Van & Savana) 1.215 (30.86)
12.50 X 1.26" Rotor ("C" & "K" Series) 1.215 (30.86)
12.50 X 1.28" Rotor (Express, G-Van, Savana & "P" Series) 1.215 (30.86)
12.50 X 1.50" Rotor ("C" & "K" Series) 1.465 (37.21)
12.50 X 1.54" Rotor (Express, G-Van, Savana & "P" Series) 1.465 (37.21)
13.75 X 1.54" Rotor ("C", "K" & "P" Series) 1.465 (37.21)
14.25 X 1.54" Rotor ("C" & "K" Series) 1.465 (37.21)
(1) Use specification stamped on rotor (if available).