Wilwood Rear GT-Slotted Brakes with Red FNSL4R Calipers — Wrangler JL (2018–2025), 13.50-Inch

The red GT-slotted JL kit is built around 13.50-inch vented rotors and radial-mount four-piston calipers. It retains the Wrangler’s existing parking-brake arrangement, so matching the original rear brake configuration remains essential. Calipers, brake rotors, master cylinders, valves, fittings and brake lines are all part of Wilwood Engineering’s range of disc brake systems and components. The Camarillo, California company was founded in 1977 by Bill Wood and designs and manufactures these products for motorsport, street-performance and specialized applications. Compatibility with the complete brake system determines the appropriate component choice.

Technical Details

• Manufacturer part number: 140-18075-R
• Rotor specification: Iron, GT Slotted, vented; 13.50 x 0.81 inches
• Caliper specification: 4-piston Forged Narrow Superlite 4R in Red Powder Coat; radial mount
• Included service pad compound: BP-22; Stainless pistons
• Caliper body material: Forged aluminum
• Hydraulic inlet: 1/8-27 NPT
• Rotor/hat wheel-stud clearance pattern(s): 5 x 5 in; 5 x 127 mm; match the installed hub/axle pattern
• Parking arrangement: retain the original parking-brake assembly
• Hydraulic brake hoses: included; DOT-approved hose kit
• Wheel clearance: 17-inch wheels may fit; verify the manufacturer’s complete caliper/rotor template for the installed wheel
• Supplied as one kit with mounting hardware; spindles, hubs, master cylinder and booster are not included

Fitment & Compatibility

Fits the listed Wrangler JL applications from 2018–2025, with trim-specific limits for Rubicon, 392, 4xe and other versions. Retain the factory parking-brake assembly and verify the exact model/trim row; the broad year range does not cover every JL configuration.

Follow DS1639 for the required dust-shield modification and caliper alignment. This JL package includes 25-inch brake hoses; check routing through full suspension travel after installation.

The table below provides the full application breakdown; match its year, model and brake-configuration details.

Manufacturer Resources

• Exact Wilwood kit specifications and wheel-clearance information
• Installation instructions and component list

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.

Ask PMB Performance to help confirm the configuration before ordering if the vehicle has modified brakes or running gear. We have over 20 years of experience with parts and fitment; a VIN plus the installed component details gives us the best starting point.

Vehicle Applications

Application Notes

1. Line kit included (manufacturer): 220-15929 (25.00 in)
2. Rear line-kit reference: 220-15929