Wilwood Rear Red AERO4 and Electric Parking Brake Conversion, Big Ford Housing, Drilled 14-Inch Rotors at 2.36-Inch Axle Offset

Red AERO4 calipers and drilled-and-slotted 14-inch rotors provide normal braking in this Big Ford rear kit. The parking function is carried by a distinct motor-driven red caliper pair operated through the included switch, harness and controller. Wilwood Engineering, founded by Bill Wood in 1977, designs and manufactures disc brake systems from Camarillo, California. Its motorsport, street-performance and specialized product range spans calipers, brake rotors, master cylinders, valves, fittings and brake lines. A conversion must be considered as a complete brake system when selecting those parts.

Technical Details

• Manufacturer part number — 140-16173-DR; supplied as one rear axle brake kit.
• Parking-brake package — Two separate electric parking calipers, control unit, switch with pigtail and universal wiring harness included; vehicle electrical connections require installation.
• Supplied service pads — BP-10 compound; verify suitability for the intended operating conditions.
• Hydraulic service calipers — AERO4; 4 pistons per caliper; Forged Aluminium body; radial mounting; Stainless pistons.
• Rotor mounting hats — Aluminum; Black E-Coat; hat offset 1.625 inches. This is a hat dimension, not the axle offset.
• Minimum nominal wheel diameter — 18 in; 457.2 mm; full spoke/barrel clearance must be checked using the installation drawing.
• Cataloged rotor/hat mounting-hole pattern — 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 bolt circle; cataloged stud-hole clearances 0.520 in; 13.21 mm. The existing hub or axle flange determines the vehicle wheel pattern and stud specification. These rotor/hat drillings do not convert that pattern.
• Caliper finish and port — Red Powder Coat; hydraulic inlet 1/8-27 NPT.
• Mechanical contents — Separate wheel hubs are not included; mounting hardware supplied; spindles not included.
• Hydraulic installation — Hydraulic lines and fittings are separate and must be selected for the vehicle; master cylinder not included; brake booster not included.
• Rear axle interface — Big Ford housing flange; 2.36 in; 59.94 mm axle offset. Measure the installed assembly.
• Rotor dimensions — 14.00 in; 355.6 mm outside diameter; 1.10 in; 27.94 mm thick.
• Rotor material and surface — Spec-37 Iron; vented; SRP Drilled & Slotted; surface finish Black Electro Coat.

Fitment & Compatibility

Match the actual rear axle to the Big Ford diagram and 2.36-inch offset before disassembly. Verify the bearing arrangement, axle register and wheel-bolt pattern independently, including any changes made during a previous axle conversion. Use the full 18-inch minimum wheel envelope for both caliper positions.

Any vehicle application in the fitment table below depends on the installed axle interface. Compare flange and bearing geometry, axle offset, center register and wheel hardware with the specified assembly. For a 1990 Lincoln Town Car, identify the actual axle and confirm the specified interface; do not select this conversion from model and year alone.

The supplied EPB switch and pigtail connect through a universal harness to the controller and separate parking-caliper motors. Vehicle-specific power, ground and ignition/accessory wiring still requires installation under DS1353. This static-hold system is independent of the service brakes and is not intended for emergency stopping.

With more than 20 years in parts, PMB Performance can help review the compatibility checks for this conversion. Include information about the axle, retained hubs and any changes from the original suspension.

Review the Installation instructions, Technical bulletin, EPB mounting and wiring instructions before selecting hardware or checking wheel clearance.

Manufacturer Warning

Applicable to brake pads only. 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.