Wilwood Drilled Rear Disc/Parking Conversion for GM 12-Bolt Factory C-Clip Axles, Black Superlite Calipers, Staggered Mounts and 2.75-Inch Offset

Drilled-and-slotted rotor rings and black calipers distinguish this version of the staggered GM 12-bolt rear kit. The internal parking shoes work inside aluminum hats, with separate hoses and vehicle cable connections required to complete the conversion. The kit comes from Wilwood Engineering of Camarillo, California, established in 1977 by Bill Wood. Wilwood designs and manufactures disc brake systems and components for motorsport, street-performance and specialized installations. Alongside calipers and brake rotors, its range includes master cylinders, valves, fittings and brake lines, all requiring selection around the complete system's operating requirements.

Technical Details

• Manufacturer: Wilwood; manufacturer part number: 140-13678-D. 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.

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

• 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.

• 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: SRP Drilled & Slotted.
• Rotor-hat material: Aluminum. Hat offset: 1.950 inches; this hat dimension is separate from axle offset.
• Rotor surface finish: Black Electro Coat.

Fitment & Compatibility

The Chevelle/442/Beaumont/Camaro/Apollo table includes front-spindle conditions that cannot establish rear fitment. Measure the 12-bolt flange and 2.75-inch offset, retain factory C-clips and verify shock clearance. Do not use with C-clip eliminators or modified special ends.

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.

Manufacturer Documents

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

Supply the vehicle details and current brake configuration when contacting PMB Performance for fitment help. Our team brings over 20 years of parts experience to checking the combination.