Wilwood Rear Black Superlite/SRP Brake Kit with EPB — 12.88-Inch Rotors, GM Six-Lug 4x4 (1971–1991)

Black FNSL4R calipers clamp drilled/slotted 12.88-inch SRP rotors in this GM rear conversion. The electric parking system has its own calipers and supplied controls, leaving the hydraulic service calipers responsible for normal braking. Wilwood Engineering’s disc brake systems and components serve motorsport, street-performance and specialized applications. Bill Wood founded the company in 1977; it is based in Camarillo, California. Wilwood designs and manufactures brake rotors and calipers as well as master cylinders, valves, brake lines and fittings. Selecting compatible components is essential to the complete system.

Technical Details

• Manufacturer part number: 140-18161-D
• Rotor specification: Spec-37 Iron, SRP Drilled & Slotted, vented; 12.88 x 1.10 inches
• Caliper specification: 4-piston Forged Narrow Superlite 4R in Black Powder Coat; radial mount
• Included service pad compound: BP-10; Stainless pistons
• Caliper body material: Forged aluminum
• Hydraulic inlet: 1/8-27 NPT
• Rotor/hat wheel-stud clearance pattern(s): 6 x 5.5 in; 6 x 139.7 mm; match the installed hub/axle pattern
• Housing/flange application: K5 Blazer / K10
• Required axle offset: 2.46 in; 62.48 mm
• Parking equipment: separate electric calipers, controller and harness included
• Hydraulic brake hoses: not included; select the correct application-specific lines/fittings
• Wheel clearance: 17-inch wheels may fit; verify the manufacturer’s complete caliper/rotor template for the installed wheel
• Supplied as one kit with mounting hardware; spindles, hubs, master cylinder and booster are not included

Fitment & Compatibility

The Superlite/EPB installation is for a measured 2.46-inch-offset GM six-lug rear axle using the documented flange. Read the individual 1971–1991 application entries for K-series pickups/Suburbans, Blazer/K5 Blazer and Jimmy. Check clearance for both the four-piston service caliper and the electric parking caliper around the 12.88-inch rotor.

DS1676 specifies a 3.55-inch axle center register, a 6 x 5.5-inch lug pattern and a flange no larger than 7.05 inches with a 0.050-inch x 45-degree chamfer. Plan the separate hydraulic line purchase and the routing of the included EPB harness before removing the original brakes.

Check the complete application table below, including its model-year splits and configuration notes.

The electric parking brake is for stationary parking, not an emergency-stop brake. Applying it while the vehicle is moving can lock the rear wheels and cause a skid. Follow the wiring and holding-test procedures in the manufacturer’s instructions.

Manufacturer Resources

• Exact Wilwood kit specifications and wheel-clearance information
• Installation instructions and component list
• Axle-offset measurement worksheet

WARNING: This product can expose you to chemicals including Arsenic, Cadmium, Chromium (Hexavalent compounds), Lead, Nickel, Cobalt and Antimony Trioxide which are known to the State of California to cause cancer or other reproductive harm. For more information go to www.p65warnings.ca.gov.

For fitment help, contact PMB Performance with your VIN and details of any axle, spindle or brake changes. Our team has over 20 years of experience checking parts and fitment, including the dimensions that a model-year search cannot establish.

Vehicle Applications

Application Notes

1. Line kit included (manufacturer): None