Wilwood Rear 12.88-Inch GT Parking Brake Package — Black Superlite, GM Six-Lug 4x4 (1971–1991)

Black Superlite four-piston calipers and 12.88-inch GT-slotted Spec-37 rotors form this GM six-lug rear brake kit. Drum parking shoes within the hats are included, while their cables and clevis connections are selected to suit the vehicle. From its base in Camarillo, California, Wilwood Engineering designs and manufactures disc brake systems for motorsport, street-performance and specialized applications. Founded by Bill Wood in 1977, the company also produces the individual calipers, brake rotors, master cylinders, valves, fittings and brake lines used in these installations. Selection should account for how each component works within the complete brake system.

Technical Details

• Manufacturer part number: 140-18160
• Service calipers: Forged Narrow Superlite 4R; 4 pistons; radial mount; Black Powder Coat
• Brake rotors: 12.88 x 1.10 inches; Spec-37 Iron; GT Slotted; vented construction
• Pads: BP-10; piston material: Stainless
• 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 brake: included internal drum/shoe assembly; cable and clevis hardware are not 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

Use this 12.88-inch Superlite rear package on the specified K5 Blazer/K10 housing flange with 2.46-inch axle offset. The table identifies the matching GM six-lug 4x4 models and year splits across 1971–1991, including the related GMC and Suburban applications. Mechanical parking-brake cables must be matched to the supplied internal shoe assemblies.

Before assembly, verify a 3.55-inch axle register and the 6 x 5.5-inch wheel-stud layout. The maximum flange diameter is 7.05 inches, with the drawing’s 0.050-inch x 45-degree edge chamfer. DS1675 explains the rotor/hat alignment and parking-shoe adjustment; cable/clevis parts and hydraulic hoses are not included.

Use the fitment table below to confirm the exact year, model, trim and installation notes.

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.

Ask PMB Performance to help confirm the configuration before ordering if the vehicle has modified brakes or running gear. We have over 20 years of experience with parts and fitment; a VIN plus the installed component details gives us the best starting point.

Vehicle Applications

Application Notes

1. Line kit included (manufacturer): None