aFe Large Bore-HD Cat-Back Exhaust System

Dodge Ram 2500 / Ram 3500 04-07 5.9L Diesel

Part #: 49-12002

Overview

The aFe Large Bore-HD Cat-Back Exhaust System is a precision-engineered performance upgrade designed specifically for 2004 to 2007 Dodge Ram 2500 and Ram 3500 trucks equipped with the 5.9L Cummins engine. This cat-back system replaces the factory exhaust with a high-flow, mandrel-bent aluminized steel setup that enhances exhaust flow, horsepower, and torque while delivering a more aggressive exhaust tone.

Ideal for truck owners who demand improved performance, durability, and sound, the Large Bore-HD system also helps reduce exhaust gas temperatures, contributing to better engine efficiency and longevity. Whether you tow heavy loads regularly or want to unlock your Ram’s full power potential, this exhaust system offers a direct-fit, durable solution engineered for heavy-duty applications.

Key Features

Every component of the aFe Large Bore-HD Cat-Back Exhaust System is designed to optimize exhaust flow and withstand demanding conditions. Key features include:

• 4-inch mandrel-bent 409 stainless steel tubing for maximum flow and structural strength
• High-flow, straight-through perforated muffler measuring 8 inches in diameter and 30 inches in length
• Includes a straight muffler delete pipe option for a more aggressive sound and increased exhaust flow
• Single side exit design tailored specifically for Dodge Ram 2500 and 3500 models
• Bayonet-style hangers with swaged ends for secure, leak-free installation using factory mounting points
• Slotted and swedged pipe ends paired with premium band clamps to ensure tight seals and prevent leaks
• Engineered to increase exhaust flow by up to 29% and reduce exhaust gas temperatures by as much as 100°F
• Durable aluminized steel construction resists corrosion and withstands harsh operating environments
• Complete hardware kit included with all necessary clamps, hangers, and detailed installation instructions
• Manufactured in the USA by aFe, a trusted leader in performance automotive parts

Construction & Design

The Large Bore-HD Cat-Back Exhaust System is crafted from premium 409 stainless steel tubing, chosen for its excellent corrosion resistance and ability to endure the high-heat conditions typical of diesel truck exhaust systems. The tubing is mandrel bent to maintain a consistent 4-inch diameter throughout the entire length, eliminating flow restrictions caused by crushed or kinked bends and ensuring smooth, unrestricted exhaust gas flow.

The system’s muffler features a straight-through, perforated design that minimizes backpressure while delivering a bold, aggressive exhaust tone. All hangers are fully welded and incorporate swaged bayonet ends that lock securely into factory mounting points, allowing for hassle-free installation that maintains factory alignment and clearance. Slotted and swedged pipe ends combined with premium band clamps guarantee a tight, leak-free seal that withstands vibration and thermal expansion.

Performance & Sound

By significantly increasing exhaust flow—up to 29% over the stock system—the aFe Large Bore-HD Cat-Back Exhaust System helps your Dodge Ram’s engine breathe more efficiently. This results in improved horsepower and torque, as well as lower exhaust gas temperatures by as much as 100°F, which can contribute to enhanced engine longevity and reliability under heavy load conditions.

The included muffler delivers a bold, aggressive sound that enhances the driving experience without excessive drone. For those seeking maximum auditory impact, the system also includes a straight muffler delete pipe that produces a louder, race-inspired exhaust note.

Installation & Fitment

This cat-back exhaust system is designed for direct bolt-on installation on 2004–2007 Dodge Ram 2500 and Ram 3500 trucks with the 5.9L Cummins engine, requiring no cutting or welding. It utilizes all factory mounting points and includes detailed instructions, premium band clamps, and fully welded hangers to ensure a secure and leak-free fit. The two-piece tailpipe design allows for easy adjustment to achieve perfect fit and alignment. Installation can typically be completed with basic hand tools and moderate mechanical experience.

What's Included

• 4-inch mandrel-bent aluminized steel tubing
• 8-inch diameter x 30-inch length straight-through perforated muffler
• Straight muffler delete pipe for aggressive sound option
• Premium band clamps
• Fully welded bayonet-style hangers
• Detailed installation instructions

Ideal For

The aFe Large Bore-HD Cat-Back Exhaust System is perfect for Dodge Ram 2500 and 3500 owners who demand enhanced performance, improved exhaust sound, and increased durability. It is especially suited for those who tow heavy loads, haul frequently, or want to upgrade their truck’s exhaust system for better throttle response and engine efficiency. Whether you’re a daily driver, weekend warrior, or work truck operator, this exhaust system delivers reliable gains and a commanding presence on the road.

aFe POWER (Advanced FLOW Engineering) offers dyno-proven intake, filtration, and exhaust upgrades aimed at measurable performance gains. The brand’s lineup is geared toward enthusiasts looking for better airflow, improved sound, and durable materials—from cold air intakes to stainless exhaust systems for street and track applications.