aFe Large Bore-HD Cat-Back Exhaust System

2003–2004 Dodge Ram 2500 / Ram 3500

Part #: 49-12005

Overview

The aFe Large Bore-HD Cat-Back Exhaust System is a high-performance upgrade designed specifically for 2003 and 2004 Dodge Ram 2500 and Ram 3500 trucks. Engineered to replace the factory exhaust with a less restrictive, mandrel-bent aluminized steel system, it enhances horsepower, torque, and exhaust flow for improved engine efficiency. This exhaust system is ideal for heavy-duty applications, including towing and hauling, where durability and thermal management are critical.

Built by aFe, a leader in performance automotive parts, this system delivers a bold, aggressive exhaust tone while maintaining reliability and longevity. It is perfect for Ram owners seeking a powerful sound and measurable performance gains without compromising factory fitment or ease of installation.

Key Features

This Large Bore-HD Cat-Back Exhaust System incorporates advanced engineering and premium materials to maximize performance and durability. Key features include:

• 4-inch mandrel-bent aluminized steel tubing for smooth, unrestricted exhaust flow
• High-flow, straight-through perforated muffler (8" diameter x 30" length) for aggressive sound and minimal backpressure
• Optional straight muffler delete pipe for maximum flow and louder exhaust note
• Bayonet-style hangers with swaged ends for secure, rattle-free installation
• Slotted and swedged pipe ends paired with premium band clamps for a tight, leak-free seal
• Increases exhaust flow by up to 29% and reduces exhaust gas temperatures by up to 100°F
• Constructed from durable 409 stainless steel for corrosion resistance and long service life
• Maintains factory mounting points and includes a 2-piece tailpipe for easy adjustment
• Tested on flow benches and dynamometers to optimize pipe diameter and muffler design
• Backed by a 2-year limited warranty for peace of mind

Construction & Design

The Large Bore-HD Cat-Back Exhaust System is crafted from premium 409 stainless steel, chosen for its excellent corrosion resistance and durability under demanding conditions. The exhaust tubing is mandrel bent to maintain a consistent 4-inch diameter throughout the system, eliminating flow restrictions caused by sharp bends. This precision bending improves exhaust gas velocity, enhancing engine efficiency and power output.

All pipes feature slotted and swedged ends to ensure secure, leak-free connections when combined with the included high-quality band clamps. The fully welded bayonet-style hangers with swaged ends lock the system firmly in place while utilizing factory mounting points for a straightforward, no-modification installation.

Performance & Sound

Designed to boost both performance and auditory experience, this cat-back exhaust system increases exhaust flow by up to 29%, contributing to improved horsepower and torque. It also lowers exhaust gas temperatures by as much as 100°F, helping maintain optimal engine operating conditions during heavy loads or towing.

The included straight-through perforated muffler delivers an aggressive, deep exhaust tone that complements the power gains without excessive drone. For enthusiasts seeking an even louder and more pronounced exhaust note, the system includes a straight muffler delete pipe option, allowing customization of sound and flow to personal preference.

Installation & Fitment

The aFe Large Bore-HD Cat-Back Exhaust System is designed for a direct bolt-on installation on 2003 and 2004 Dodge Ram 2500 and Ram 3500 models. It uses all factory mounting points and includes detailed installation instructions, clamps, and hangers to ensure a secure and leak-free fit. The two-piece tailpipe design allows for easy adjustment to achieve proper alignment and clearance.

No cutting or welding is required, making this system an accessible upgrade for experienced DIYers or professional installers alike.

What's Included

• 4-inch mandrel-bent aluminized steel exhaust tubing
• 8" diameter x 30" length straight-through perforated muffler
• Straight muffler delete pipe
• Premium band clamps for secure connections
• Fully welded bayonet-style hangers
• 2-piece adjustable tailpipe
• Detailed installation instructions

Ideal For

This exhaust system is ideal for Dodge Ram 2500 and 3500 owners from model years 2003 to 2004 who demand enhanced engine performance, improved exhaust sound, and increased durability. It is especially suited for heavy-duty truck users who tow or haul regularly and want to reduce exhaust gas temperatures while gaining horsepower and torque. Enthusiasts looking for a bold, aggressive exhaust note without sacrificing reliability will also appreciate this upgrade.

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.