Wilwood 140-18271-R FNSL4R/MC4 Big Brake Rear Axle Kit with 13.50" Rotors

The Wilwood 140-18271-R is a complete FNSL4R/MC4 Big Brake Rear Axle Kit designed to deliver high-capacity stopping power while retaining a fully functional parking brake. Engineered for performance-driven builds, this kit is an ideal complement to front big brake upgrades on high-performance and customized vehicles.

At the heart of this kit is the Forged Superlite FNSL4R 4-piston caliper, paired with an oversized 13.50" vented rotor and the MC4 parking brake assembly—providing a seamless integration of high-performance braking and a dependable mechanical parking brake in a single rear axle solution.

Key Features:

• FNSL4R 4-Piston Forged Aluminum Caliper — Lightweight, rigid construction for consistent, fade-resistant braking
• 13.50" Oversized Vented Rotor — Available in slotted or drilled/slotted configurations for enhanced heat dissipation
• MC4 Integrated Parking Brake Assembly — Mechanical parking brake actuation without the need for a separate drum-in-hat setup
• BP-10 or BP-20 Compound Brake Pads — BP-10 for street performance; BP-20 for higher-friction track and autocross use
• Matched to OE master cylinder output, ABS function, and individual vehicle brake bias requirements
• Designed to complement big wheel, tire, and suspension upgrades on modified platforms
• Bolt-on fitment for 1989–1998 Nissan 240SX (S13 and S14 chassis)

The FNSL4R/MC4 rear kit is engineered to work in harmony with Wilwood's front big brake kit lineup, ensuring proper brake bias across the axles. Whether upgrading for street performance, autocross, or track day use, this kit delivers the durability, stopping power, and clean aesthetic expected from a Wilwood big brake system.