Wilwood Street Performance AERO4 BB Rear P-Brake Kits, Drilled, Red For 12 Bolt Chevy, C-Clip, 2.81 Offset, 14.00 Rotor

The Wilwood AERO4 Big Brake Rear Axle Kit (Part #140-10943-DR) upgrades the rear brakes on vehicles using a 12 Bolt Chevy rear axle with factory C-clip axles and a 2.81" offset. This kit features large, vented, and drilled 14.00" rotors for significant thermal management and braking power, along with four-piston Aerolite 4R callipers for higher and more consistent clamping force. The system uses high-friction BP-20 pads suitable for both street and performance driving and maintains the original parking brake assembly. All components are designed for compatibility with factory master cylinders and ABS systems, ensuring correct brake bias and integration. Installation hardware and adapters are included to fit a variety of axle flange patterns, prioritising precision, reliability, and factory-matched performance.

KEY SPECIFICATIONS

- Brake System: Rear disc/drum internal parking brake kit
- Fitment: 12 Bolt Chevy with factory C-clip axles, 2.81" axle offset
- Rotor: 14.00" diameter, 1.10" thick, vented and drilled
- Caliper: Aerolite 4R, 4-piston, radial mount
- Pad Type: BP-20 high friction compound
- Hat Pattern: 5x4.50/4.75/5.00, 1.95" offset, 12x8.75" bolt circle
- Axle Stud: 0.50" diameter required
- Maximum Axle Flange: 6.61" with .050" x 45° chamfer
- Parking Brake: Utilizes existing OE cable system

INSTALLATION SUMMARY

This kit should be installed by someone familiar with disc brake systems. Confirm wheel-to-caliper clearance (minimum 0.080") and verify axle flange, stud diameter, and offset before installation. Old brakes must be fully removed and parts cleaned before assembly. Use Loctite 271 on other fasteners and follow Wilwood's torque specs. Hydraulic lines, parking brake cables, and related hardware are not included and must be sourced separately if needed. Pads, rotors, and callipers are installed with shims and spacers for proper alignment. Bleed the system with the recommended fluid and follow Wilwood’s pad and rotor bed-in process. Repeat installation for both rear wheels.

FACTORY FIT NOTES

- Direct fit for 12 Bolt Chevy axles with stock C-clip and 2.81" offset
- Requires 0.50" diameter axle studs—oversized studs need hats machined
- Axle flange diameter max is 6.61"; check for aftermarket axles
- Shock or suspension modifications may be needed for some setups
- Maintain minimum 0.080" wheel-to-caliper clearance
- Does not include brake lines or parking brake hardware