Ram 1500 TRX 2021-2023 Street Challenge Rear Brake System

Serious Stopping Power for the Most Powerful Ram Ever Built

The Ram 1500 TRX puts 702 horsepower behind a full-size truck, and the factory rear brakes are working overtime to keep that supercharged Hellcat power in check. The Rotora RFK.591.04 Street Challenge Rear Brake System replaces the stock setup with a 4-piston RF410 forged monobloc caliper and a 405x32mm 2-piece floating rotor, giving TRX owners the pedal feel, fade resistance, and stopping consistency the truck deserves whether it is hauling, towing, or blasting through the desert.

Key Features

• 4-piston RF410 forged monobloc rear calipers for maximum clamping force and rigidity
• 405x32mm 2-piece floating rotors reduce unsprung weight and manage heat under hard braking
• Available in slotted or drilled rotor configurations to match your driving style
• Ten color options including a premium Zinc natural anodize finish
• Direct bolt-on design engineered specifically for the 2021-2023 Ram 1500 TRX
• Includes all hardware, lines, and pads needed for a complete rear brake upgrade
• Backed by a 1-year Rotora warranty

Fitment

Specifications

What's Included

• 2x RF410 forged monobloc rear calipers
• 2x 405x32mm 2-piece floating rotors
• Braided stainless brake lines
• Mounting brackets and hardware kit
• Performance brake pads

About Rotora

Rotora designs and manufactures high-performance big brake kits for street, track, and off-road applications. Every RFK.591.04 kit is built around forged monobloc calipers and 2-piece floating rotors engineered to handle sustained heat and repeated hard stops without losing pedal feel. Rotora components are developed and tested to deliver consistent, fade-resistant braking for demanding vehicles like the Ram 1500 TRX.

FAQ

What is the RFK.591.04?

The RFK.591.04 is a Rotora Street Challenge rear brake system for the 2021-2023 Ram 1500 TRX, featuring 4-piston RF410 forged monobloc calipers and 405x32mm 2-piece floating rotors. It is a direct bolt-on upgrade that replaces the factory rear brakes for improved stopping power and heat management.

Should I choose slotted or drilled rotors?

Slotted rotors clear gas and debris from the pad surface and hold up well under sustained heavy use, making them a strong choice for towing or track days. Drilled rotors offer sharper initial bite and a more aggressive look but are typically better suited to lighter street use since they can be more prone to stress cracking under extreme heat.

What color options are available for this kit?

This kit is offered in Natural Anodize (Zinc), Red, Orange, Yellow, Green, Light Metallic Blue, Dark Metallic Blue, Silver, Black Hard-Anodize, and White, so you can match the calipers to your truck's look.

What years does this kit fit?

This Rotora rear brake system is designed specifically for the 2021-2023 Ram 1500 TRX and is not intended for standard Ram 1500 models.

Why does the Zinc finish cost more than the other colors?

The Zinc natural anodize finish uses a more involved anodizing process than the standard color finishes, which is why it carries a higher price point than the other nine available colors.

How difficult is installation?

Installing this rear brake system requires intermediate to advanced mechanical skill and standard hand tools. Most experienced installers or shops can complete the rear brake swap in a few hours, though professional installation is recommended if you are not comfortable with brake system work.

Is there a break-in procedure for new brakes?

Yes. New pads and rotors should be broken in with a series of moderate stops from around 45 mph down to 10 mph, allowing full cooling between stops, and avoiding hard braking or extended highway driving for the first 200 to 300 miles.

Are aftermarket brake pads compatible with this kit?

This kit ships with performance pads matched to the RF410 caliper. Replacement pads sized for the RF410 caliper will fit, but it is best to confirm pad compatibility with Rotora before sourcing pads from other brands.

How many pistons does the caliper have?

Each RF410 rear caliper in this kit uses a 4-piston forged monobloc design for even, consistent clamping force across the rotor.

What size are the rotors?

The kit uses 405x32mm 2-piece floating rotors, sized specifically to work with the RF410 caliper and clear the TRX's factory wheels.

What warranty comes with this brake system?

The RFK.591.04 is backed by a 1-year Rotora warranty covering manufacturing defects in the calipers and rotors.

Install Instructions

1. Park the truck on a level surface, engage the parking brake, and loosen the rear wheel lug nuts before lifting the vehicle and securing it on jack stands.
2. Remove the rear wheels and disconnect the factory brake line from the caliper, capping it to prevent fluid loss and contamination.
3. Remove the factory caliper, bracket, and rotor, then clean the hub and axle mounting surfaces thoroughly.
4. Install the new mounting brackets supplied with the kit, torquing all hardware to manufacturer specification.
5. Mount the new 405x32mm rotor onto the hub, followed by the RF410 caliper and pads, and secure with the provided hardware.
6. Connect the new braided stainless brake lines to the caliper and to the factory hard line, then bleed the brake system to remove all air.
7. Reinstall the wheels, torque the lug nuts to spec, and lower the vehicle.
8. Check fluid level, pump the brake pedal to confirm firm engagement, and road test at low speed before returning to normal driving.
9. Follow the recommended break-in procedure for the first 200 to 300 miles before subjecting the brakes to hard use.

WARNING: This product can expose you to chemicals including brake dust, which is known to the State of California to cause cancer. For more information go to www.P65Warnings.ca.gov.