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Product details
This red rear assembly uses GT-slotted Spec-37 rotor rings with Superlite 4R calipers. The hats carry the specified wheel pattern and enclose a mechanical parking brake for the measured Big Ford housing end. Wilwood Engineering’s work covers the design and manufacture of disc brake systems for motorsport, street-performance and specialized applications. Bill Wood founded the company in 1977 in a business now based in Camarillo, California. Its calipers, master cylinders, brake rotors, brake lines, valves and fittings must be selected around the complete system.
Technical Details
- Manufacturer part number: 140-13323-R
- Application and package: Rear Brake Kits - Street Performance; Rear Kits; Disc; Parking; Sold as a kit.
- Stud-hole / clearance provision: 0.640 in; 16.26 mm; diameter provision, not a thread designation
- Wheel diameter starting requirement: 17 in; 431.8 mm; verify the individual wheel against the installation drawing
- Rear axle-end interface: Big Ford Bronco; axle/flange offset 2.36 in; 59.94 mm
- Included mechanical components: Mounting hardware: Yes; hub(s): No; spindle(s): No
- Hydraulic components supplied: Master cylinder: No; brake booster: No; brake lines: No
- Specified pad compound: BP-10
- Separate rotor-hat specification: Iron; Black E-Coat; offset 1.540 inch; part 170-13326
- Rotor dimensions: 12.88 in; 327.15 mm outside diameter; 1.10 in; 27.94 mm thickness
- Rotor construction: Spec-37 Iron; Vented; GT Slotted
- Caliper assembly: Forged Narrow Superlite 4R; 4 pistons per caliper; Forged Aluminium body; Radial mount
- Piston and finish specification: Stainless pistons; Red calipers; Red Powder Coat
- Hydraulic inlet: 1/8-27 NPT
- Wheel bolt pattern(s): 5 x 5.5 in; 5 x 139.7 mm
Fitment & Compatibility
Check DS1018 against the actual Bronco-style Big Ford axle flange. Confirm offset, register and wheel clearance before adapting the separate parking cables or selecting hose length.
The hat and axle interface need three independent checks: the housing-end pattern, the specified offset and the illustrated 2.88-inch register/centering arrangement. Flange diameter is limited to 6.61 inches; the drawing also calls for a 45-degree chamfer measuring 0.050 inch.
The installation reference identifies Big Ford Bronco rear applications with 3300-lb axle/11-inch drums for 1966–1975 and the listed 1976–1977 configurations. Verify the actual flange,2.36-inch offset and axle register.
Hydraulic hoses/fittings and parking-brake cables, adapters and cable hardware are not included. Choose a compatible cable arrangement for the internal parking brake; universal cable systems may require vehicle or cable modifications.
Manufacturer References
- Wilwood exact kit specifications
- Wilwood installation instructions DS1018
- Axle measurement worksheet
With more than 20 years of parts and fitment experience, PMB Performance can help compare the existing brake assembly with the required component.
