Wilwood Red-Caliper Rear GT Brake and Parking Kit for GM 12-Bolt Factory C-Clip Axles with 2.75-Inch Offset and Staggered Shock Mounts

This red GT configuration converts the specified GM 12-bolt rear end to four-piston service brakes with an internal-shoe parking system. Its aluminum hats and staggered caliper mounts must correspond to the measured axle offset and housing end. Wilwood Engineering's product range serves motorsport, street-performance and specialized brake applications. Founded in 1977 by Bill Wood and based in Camarillo, California, the company designs and manufactures disc brake systems, calipers, rotors, master cylinders, valves, fittings and brake lines. Individual components must be selected to match the complete system rather than by appearance alone.

Technical Details

• Wheel interface: 5 x 4.5 in; 5 x 114.3 mm; 5 x 4.75 in; 5 x 120.65 mm; 5 x 5 in; 5 x 127 mm. Rotor/hat wheel-stud clearance: 0.520 in; 13.21 mm.
• Nominal minimum wheel diameter: 17 in; 431.8 mm. Verify the full wheel-clearance drawing; diameter alone does not establish barrel or spoke clearance.
• Housing/spindle flange: 12 Bolt. Flange/axle offset: 2.75 in; 69.85 mm.

• Manufacturer: Wilwood; manufacturer part number: 140-13678-R. Supplied quantity: Sold as a kit.
• Application category: Rear Brake Kits - Street Performance. Axle/spindle category: Rear Kits. Brake function: Disc; Parking.
• Separate wheel hubs included: No. Retain only the hub arrangement specified for this kit.
• Mounting hardware included: Yes. Spindles included: No. Master cylinder included: No. Brake booster included: No.
• Flexible brake lines included: No. Select the vehicle-end connection and routing separately.
• Internal parking-shoe assemblies are included. The vehicle cable/clevis connection is separate; parking cable kit 330-9371 is a separately selected option, not included.

• Rotor: 12.88 in; 327.15 mm outside diameter; 1.10 in; 27.94 mm thickness. Material: Spec-37 Iron. Construction: Vented. Friction-face style: GT Slotted.
• Rotor-hat material: Aluminum. Hat offset: 1.950 inches; this hat dimension is separate from axle offset.
• Rotor surface finish: Black Electro Coat.

• Calipers: 4 stainless pistons per caliper; radial mounting; forged aluminium bodies. Color: Red. Finish: Red Powder Coat. Inlet thread: 1/8-27 NPT.
• Caliper family: Forged Narrow Superlite 4R. Brake-pad compound: BP-10.

Fitment & Compatibility

DS1053 calls for factory C-clips and 2.75 inches of axle offset, with the right caliper behind and left caliper ahead of the axle. Confirm the rear application separately from the front-spindle conditions in the Chevelle/442/Beaumont/Camaro/Apollo rows. Hoses and parking cables are additional parts.

For staggered shock mounts, the right-hand caliper mounts behind the axle and the left-hand caliper ahead of it. Verify this orientation against the shock and suspension clearance.

Factory OE C-clip retention is required; special housing ends and C-clip eliminators are excluded. Separate flexline options are 220-7056 (14 inches), 220-7699 (16 inches) and 220-8307 (18 inches). A universal parking-cable installation may require cable or vehicle modifications.

Use the fitment table below for the complete model, year, submodel and brake-option conditions; every listed condition must match the installed vehicle.

Manufacturer Documents

• Wilwood product specifications and wheel-clearance drawing
• Installation instructions
• Technical bulletin

PMB Performance brings over 20 years of parts and brake-fitment experience to helping you select the correct configuration. Send the vehicle details and measured brake interfaces if you need help confirming this kit.