2018+ Jeep Wrangler MRT Trail Rated JL4 Axle Back

Jeep Wrangler JL4 Trail Rated Axle-Back Exhaust System

Refined Performance Sound for 4-Door Wrangler JL Models

Enhance your 2018+ Jeep Wrangler JL 4-door with MRT's Trail Rated axle-back exhaust system, engineered specifically for four-door models seeking refined performance sound without excessive loudness. This premium exhaust delivers on-demand performance character with dual 4-inch tips that combine sophisticated styling with enhanced exhaust flow.

Constructed from corrosion-resistant T304 stainless steel with precision mandrel-bent 2.5-inch tubing, the Trail Rated system optimizes exhaust flow while maintaining tolerable drone levels for comfortable daily driving. Choose between classic polished stainless steel tips or tactical Black Ops matte ceramic finish to match your Wrangler's aesthetic.

Performance and Sound Characteristics

On-Demand Performance Sound

• Idle: Refined, confident presence with subtle performance character
• Cruising: Civilized exhaust note with minimal intrusion
• Acceleration: Spirited, fun performance sound that engages the driver
• Wide Open Throttle: Full performance tone with enhanced depth and character

The Trail Rated system delivers performance sound when you demand it while maintaining composure during relaxed driving. The refined acoustic tuning ensures you enjoy enhanced exhaust character without the excessive loudness or constant drone that can make other performance exhausts fatiguing on long trips.

Enhanced Flow and Power Delivery

The straight-through muffler design with 2.5-inch mandrel-bent tubing significantly reduces exhaust restriction compared to the factory system. This optimized flow path allows exhaust gases to exit more efficiently, reducing backpressure and extracting additional horsepower and torque from the 3.6L Pentastar V6 engine.

With a performance rating of 8 out of 10, drivers experience noticeable improvements in throttle response and acceleration across the RPM range. The enhanced exhaust flow allows the engine to breathe more freely, optimizing power delivery for both off-road trails and highway merging situations.

(Refer to Technical Specs & Features tab for more information)

Technical Specifications

Part Number: 90R139
Application: 2018+ Jeep Wrangler JL 3.6L and 2.0L 4XE (4-Door only)
Installation Time: 60 minutes
Warranty: Limited Lifetime

Product Features

• Material: Corrosion-resistant T304 stainless steel construction
• Tubing Diameter: 2.5-inch mandrel-bent for maximum flow
• Tip Style: Dual 4-inch double-wall with beveled edges
• Tip Finish Options: Polished steel or Black Ops matte ceramic
• Muffler Design: Straight-through configuration for reduced restriction
• Manufacturing: Assembled in Plymouth, Michigan
• Hardware: Complete installation kit included
• Compatibility: 2018+ Wrangler JL 4-door models only

Performance Ratings

• Loudness: 9/10 - Refined performance sound with on-demand character
• Drone: 3/10 - Noticeable but tolerable cabin resonance
• Performance: 8/10 - Significant gains in flow and power
• Daily Drivability: 9/10 - Excellent balance of performance and comfort

• What is the muffler design? Straight through design to provide maximum exhaust gas flow.
• What is the tube diameter? A large 2.5" tube is used for reduced exhaust flow restrictions.
• What are the performance gains? Reducing restriction and maximizing flow provides for noticeable gains.

• What kind of tip is it? Dual 4"double wall T304 stainless steel tips with beveled edges.
• What are my tip finish options? Stylish Polished Stainless Steel or Black Ops Matte Ceramic.
• How do I get noticed? Great sound and great looks turn heads and get positive comments!

• DIY installation for the backyard mechanic
• T304 Stainless Steel for the best corrosion resistance
• Engineered, designed and manufactured in the USA

Premium Construction and Engineering

T304 Stainless Steel Excellence

Constructed entirely from premium T304 stainless steel, the Trail Rated exhaust system withstands harsh conditions including mud, water, salt, and extreme temperature fluctuations. This corrosion-resistant material ensures your exhaust maintains its appearance and performance for years, even under demanding off-road and all-weather use.

The precision mandrel-bent tubing provides smooth, unrestricted exhaust flow without the crimped sections found in inferior crush-bent designs. This manufacturing process maintains consistent internal diameter throughout the system, maximizing performance while ensuring structural integrity and durability.

Dual 4-Inch Double-Wall Tips

The dual 4-inch exhaust tips feature premium double-wall construction with beveled edges for sophisticated styling and long-term durability. The double-wall design prevents heat discoloration of the outer wall while creating visual depth that single-wall tips cannot match. Each tip is precision-crafted to exact specifications, ensuring perfect alignment and symmetrical appearance on your 4-door Wrangler.

American Manufacturing and Warranty

Engineered in Michigan

Every Trail Rated exhaust system is engineered and designed at MRT's Plymouth, Michigan facility, ensuring consistent quality control and meticulous attention to detail. The American manufacturing process allows MRT to maintain strict standards for welding quality, fitment precision, and overall construction excellence that mass-produced imports cannot match.

Limited Lifetime Warranty

MRT backs the Trail Rated exhaust system with a limited lifetime warranty covering defects in materials and workmanship for as long as you own your Jeep Wrangler JL. This comprehensive warranty protection reflects MRT's confidence in premium materials, manufacturing processes, and American-made craftsmanship.

Installation and Fitment

4-Door Specific Engineering

The Trail Rated exhaust system (Part #90R139) is engineered exclusively for 2018+ Jeep Wrangler JL 4-door models equipped with the 3.6L Pentastar V6 engine. The system accounts for the longer wheelbase and unique exhaust routing of 4-door models, ensuring proper fitment and optimal acoustic performance.

Important: For 2-door Wrangler JL models, use MRT Part #90R140, which is specifically designed for the shorter wheelbase configuration.

Simple DIY Installation

MRT engineers designed the Trail Rated system for straightforward do-it-yourself installation in approximately 60 minutes using common hand tools. The precision-engineered design ensures proper fitment with factory mounting points, and all necessary hardware is included with your purchase.

No welding or modifications are required for installation. The system connects directly to factory connection points, making it accessible for weekend DIY enthusiasts and backyard mechanics.

Installation Requirements:

• Tools Needed: Basic hand tools (wrenches, sockets, jack stands)
• Vehicle Lift: Recommended but not required (can be installed with jack stands)
• Skill Level: Beginner to intermediate DIY mechanic
• Time: Approximately 60 minutes

Professional Installation Available

Located near Plymouth, Michigan? Schedule professional installation at MRT's facility by calling 734-455-5807. Expert technicians ensure perfect fitment and optimal performance while you wait.

Installation Questions:

• Can I install this myself? Yes, MRT engineers this Premium Exhaust System for a simple do-it-yourself (DIY) installation.
• How long does it take to install? Installation time is about 1 hour and requires only common hand tools.
• What is included? All necessary hardware included.