Wilwood Front GT Rotor/Hub System for GM Second-Generation AFX ProSpindles, 12.88-Inch Rings with Black Superlite Six-Piston Calipers (Listed 1970–1990 Applications)

Black Superlite 6R calipers and 12.88-inch GT rotors form this front hub kit for the documented second-generation AFX ProSpindles. Separate aluminum hats and hubs are included, with BP-20 pads specified for the GT rotor option. The six-piston radial caliper requires adequate spoke clearance beyond the nominal 17-inch wheel size. Identify the actual Wilwood spindle before choosing among the listed GM model/year applications. Bill Wood founded Wilwood Engineering in 1977; the company is based in Camarillo, California. It designs and manufactures calipers, brake rotors, master cylinders, valves, fittings and brake lines for motorsport, street-performance and specialized applications. This kit is one configuration within that disc-brake-system range and must be matched to the vehicle build.

Technical Details

• Manufacturer part number: 140-15982. Quantity: one kit for the stated axle/application.
• Rotor specification: 12.88-inch outside diameter × 1.10-inch thickness; GT slotted faces. Spec-37 Iron construction; GT 48 Curved Vane design; published vane configuration: 48 CV.
• Service caliper: Forged Narrow Superlite 6R; 6 pistons; stainless piston material. Radial mounting, black powder coat finish.
• Rotor hats: aluminum, black e-coat finish; Big Brake Hat - Flared Bell. Hat offset: 1.500 inch.
• Supplied hub assembly: Hub - Hat Mount, aluminum, bare finish.
• Wheel mounting patterns: 5 x 4.50; 5 x 4.75 inches.
• Published piston bores: 1.62, 1.12, 1.12 inches. Supplied pad compound: BP-20.
• Caliper hydraulic inlet: 1/8-27 NPT.
• Brake hoses are not included. Manufacturer line-kit reference(s), sold separately: 220-10509.
• Minimum nominal wheel diameter: 17 inches. The wheel must also clear the actual caliper and rotor profile in the installation drawing.
• Mounting hardware and the specified pads are included. Spindles, master cylinder and brake booster are not supplied.

Fitment & Compatibility

Use this kit on the listed GM applications equipped with Wilwood second-generation AFX ProSpindles. Do not assume that original spindles or the earlier AFX spindle are interchangeable. Match the model, production year and spindle option in the application table, then verify the installed spindle, hub bolt circle, full wheel seating and actual spoke/barrel clearance. Match the front caliper volume and pad compound to the master cylinder and rear brakes, and supply suitable braided flexlines separately. Use the complete application table below for the individual year, submodel, brake configuration and note attached to each entry.

For fitment assistance, send PMB Performance the vehicle details together with the installed spindle or axle configuration and wheel measurements. We draw on 20+ years of parts and fitment experience to help assess the combination.

Manufacturer documentation: Installation instructions.

Manufacturer Warning

Applicable to brake pads only: Wilwood warns of exposure to arsenic, cadmium, hexavalent chromium compounds, lead, nickel, cobalt and antimony trioxide, chemicals known to California to cause cancer or reproductive harm. More information: P65Warnings.ca.gov.