Wilwood Right Black Aero4 Brake Caliper, 1.62/1.38-Inch Bores / 1.25-Inch Rotor Width

This black right-hand Wilwood AERO4 has four stainless pistons with differential 1.62/1.38-inch bores. A forged body, internal fluid passages and a 7.09-inch radial pattern define this nominal 1.25-inch rotor-width configuration. Founded in 1977 by Bill Wood, Camarillo, California-based Wilwood Engineering designs and manufactures disc braking systems. Its motorsport, street-performance and specialized range covers calipers, brake rotors, master cylinders, valves, fittings and brake lines, selected as parts of a complete system.

Technical Details

• Manufacturer part number: 120-13281-BK. Component: Aero4 Radial Mount caliper.
• Supply: one brake caliper, not a complete axle brake kit. Match the mating rotor, pads, bracket and connection hardware to the installation.
• Black powder coat finish on a forged aluminum caliper body.
• Hydraulic inlet thread: 1/8-27 NPT. Use a fitting with the correct thread and sealing seat.
• The rotor channel is specified for 1.25-inch nominal width. Rotor outside diameter: 12.19 to 15.00 inches. Specified rotor-width limits: 1.10–1.28 inch.
• 7.09-inch radial mounting pattern, right hand; mounting height 2.09 inches and hole size 0.45 inch.
• Piston dust boots: not fitted.
• Caliper weight: approximately 6.9 lb.
• Brake pad profile 6617; select friction material for the actual operating conditions.
• 4 stainless steel pistons with 1.62/1.38-inch bore groups. The specified effective area is 3.56 sq in.

Fitment & Compatibility

Check the right-side bracket against the 2.09-inch mount height and required rotor centerline. Confirm the type 6617 pad outline and usable rotor diameter before evaluating the final wheel clearance.

PMB Performance has over 20 years of brake-component experience. Send the existing caliper identification, rotor measurements and bracket details for help matching this configuration.