OAO Valvetronic Cat-Back Exhaust System for Mercedes-Benz W166 GL63 / GLE63 / GLS63 AMG 5.5L M157 V8 Biturbo

Unleash the Power of the AMG M157 V8

Designed for the Mercedes-AMG W166 GL63, GLE63, and GLS63 equipped with the legendary 5.5L M157 twin-turbocharged V8 engine, the OAO Valvetronic Cat-Back Exhaust System is engineered to deliver a deeper, louder, and more aggressive AMG soundtrack while maintaining the refined driving experience expected from a premium performance SUV.

Combining high-flow exhaust engineering with electronically controlled valves, the OAO system gives you complete control over the vehicle's exhaust character.

Keep the valves closed for a refined and controlled sound during everyday driving, or open them to unleash the full character of the M157 V8.

Manufactured from premium T304 stainless steel with precision TIG welding, mandrel-bent tubing, and high-flow muffler technology, the OAO system delivers excellent durability, heat resistance, and performance-focused craftsmanship.

Key Features

✓ Designed for Mercedes-AMG W166 GL63 / GLE63 / GLS63

✓ 5.5L M157 Twin-Turbocharged V8 Engine

✓ Valvetronic Cat-Back Exhaust System

✓ Electronic Exhaust Valve Control

✓ Premium T304 Stainless Steel Construction

✓ High-Flow Performance Muffler Design

✓ Precision TIG Welded

✓ Mandrel-Bent Exhaust Tubing

✓ Optimized Exhaust Gas Flow

✓ Reduced Exhaust Restriction

✓ Enhanced AMG V8 Exhaust Sound

✓ Performance-Oriented Direct-Fit Design

Intelligent Valvetronic Exhaust Control

The OAO electronic valve system allows you to change the exhaust character according to your driving conditions.

Comfort Mode

With the valves closed, the system provides a deeper but controlled exhaust tone for comfortable everyday use.

Ideal for:

• Daily Commuting

• Highway Cruising

• Long-Distance Touring

• Residential Areas

• Reduced Exhaust Volume

• Comfortable SUV Driving

Enjoy the performance character of the AMG V8 while maintaining a refined cabin environment.

Sport Mode

Open the valves and unleash the aggressive character of the M157 twin-turbo V8.

Experience:

• Increased Exhaust Volume

• Deeper V8 Exhaust Tone

• Stronger Turbocharger Acoustics

• Sharper Acceleration Sound

• More Aggressive Downshift Acoustics

• Enhanced High-RPM V8 Character

• More Emotional AMG Driving Experience

The valve-controlled design allows you to transform the character of your AMG SUV whenever you want.

Performance-Oriented Cat-Back Design

The OAO Cat-Back Exhaust System replaces the rear exhaust section with a high-flow performance configuration designed to improve exhaust efficiency and enhance the overall driving experience.

Potential benefits may include:

• Improved Exhaust Gas Flow

• Reduced Exhaust Backpressure

• Sharper Throttle Response

• Enhanced Turbocharger Sound

• Improved High-RPM Exhaust Flow

• Reduced Exhaust System Weight

• Stronger V8 Exhaust Acoustics

• Better Compatibility with Performance Downpipes

• Improved Overall Exhaust Efficiency

Actual performance gains may vary depending on vehicle configuration and supporting modifications.

Engineered for the M157 5.5L V8 Biturbo

The M157 is renowned for its massive torque delivery, strong turbocharged performance, and unmistakable AMG V8 character.

The OAO Valvetronic Exhaust is engineered around the high exhaust flow and high-temperature characteristics of this powerful V8 platform.

Key design considerations include:

• High-Flow Exhaust Routing

• Smooth Exhaust Gas Transitions

• Optimized Tubing Diameter

• Reduced Internal Turbulence

• High-Temperature Resistance

• Performance-Tuned Muffler Design

• Precision Electronic Valve Integration

The system is designed to complement both stock and modified M157 applications.

Enhanced AMG V8 Sound

The M157 twin-turbo V8 delivers a powerful and muscular exhaust character.

The OAO Valvetronic system enhances that personality with a carefully tuned performance soundtrack:

• Deeper Cold Start

• Richer V8 Exhaust Tone

• Stronger Turbocharger Acoustics

• Sharper Throttle Blips

• More Aggressive Acceleration Sound

• Enhanced Downshift Acoustics

• Stronger High-RPM V8 Character

• More Pronounced AMG Performance Sound

With the valves open, the system produces a commanding V8 soundtrack that matches the aggressive personality of the GL63, GLE63, and GLS63.

Premium T304 Stainless Steel Construction

Manufactured from high-quality T304 stainless steel to withstand high exhaust temperatures and demanding performance conditions.

Advantages include:

• Excellent Corrosion Resistance

• Superior Heat Resistance

• High Structural Strength

• Lightweight Performance Construction

• Precision TIG Welding

• CNC-Machined Connections

• Long Service Life

• Premium Surface Finish

Every OAO exhaust system undergoes quality inspection before shipment to ensure accurate dimensions, consistent welding quality, and precise fitment.

Performance SUV Styling

The OAO exhaust system is designed to complement the aggressive appearance of the AMG SUV platform.

Optional exhaust tip finishes may include:

• Carbon Fiber Exhaust Tips

• Titanium Burnt Exhaust Tips

• Polished Stainless Steel Tips

• Matte / Dark Performance Tips

The upgraded exhaust tips provide a more distinctive and performance-oriented rear appearance.

Vehicle Fitment

Compatible with applicable Mercedes-AMG models equipped with the M157 5.5L twin-turbo V8:

Mercedes-AMG GL63

• W166 GL63 AMG

• 5.5L M157 V8 Biturbo

Mercedes-AMG GLE63

• W166 GLE63 AMG

• 5.5L M157 V8 Biturbo

Mercedes-AMG GLE63 S

• W166 GLE63 S AMG

• 5.5L M157 V8 Biturbo

Mercedes-AMG GLS63

• X166 GLS63 AMG

• 5.5L M157 V8 Biturbo

Model Years

Fitment may vary depending on model year, body style, drivetrain, market specification, and factory exhaust configuration.

Please verify your exact vehicle model, production year, engine configuration, and factory exhaust layout before ordering.

Package Includes

• OAO Valvetronic Cat-Back Exhaust System

• Electronic Valve Control Module

• Wireless Remote Controller

• Exhaust Installation Hardware

• Clamps / Connection Components

• Protective Packaging

Installation

Designed as a direct-fit cat-back exhaust upgrade utilizing factory mounting locations and exhaust connection points.

No permanent cutting or welding is required for standard installation.

Professional installation is recommended to ensure proper alignment, sealing, and valve operation.

Compatible Performance Upgrades

The OAO M157 Valvetronic Cat-Back Exhaust System can be combined with:

• OAO M157 Performance Downpipes

• High-Flow Downpipes

• Performance Air Intake

• ECU Performance Calibration

• Turbocharger Upgrades

• Intercooler Upgrades

• Carbon Fiber Exhaust Tips

• Titanium Exhaust Tips

A properly matched performance setup can further enhance exhaust flow, turbocharger response, and overall AMG sound character.

Important Notes

This product is designed for performance, off-road, or motorsport applications where permitted by local regulations.

Please verify local emissions and noise regulations before purchasing or installing this product.

Sound and performance characteristics may vary depending on downpipes, catalysts, ECU tuning, valve settings, and other vehicle modifications.

Vehicle compatibility may vary by model year, body style, drivetrain, and regional specification. Please confirm fitment before ordering.

Why Choose OAO Performance

OAO Performance specializes in premium exhaust systems and performance components for Mercedes-AMG, BMW M, Audi RS, Porsche, Ferrari, Lamborghini, Jaguar, Land Rover, Aston Martin, Nissan GT-R, Chevrolet Corvette, and other high-performance vehicles.

Every OAO exhaust system combines advanced engineering, premium materials, precision TIG welding, electronic valve technology, and rigorous quality control to deliver exceptional fitment, durability, and sound.

Upgrade your Mercedes-AMG GL63, GLE63, or GLS63 with the OAO Valvetronic Cat-Back Exhaust System and experience the full character of the M157 5.5L V8 Biturbo — from refined everyday cruising to an aggressive, commanding AMG performance soundtrack.