STILLEN 504391 Pipe Axle Cat Conversion

( Brand: Stillen ), ( Type: Exhaust Systems ), ( Manufacturer Part Number: 504391 ), ( Manufacturer Warranty: Yes )

Review STILLEN Nissan Mid Pipe Axle back To Cat Conversion fits MAXIMA 2016–2021

Introducing the Stillen 504391 Axle-Back Cat-Back Exhaust System for Nissan Maxima models from 2016 to 2021, a high-performance enhancement that delivers an exceptional driving experience. This exhaust system is meticulously crafted to replace the factory exhaust, providing a more powerful and dynamic exhaust note while improving overall vehicle performance.

The Stillen Cat-Back Exhaust System is a 4-inch diameter system, significantly larger than the stock 3-inch diameter exhaust. This increase in diameter reduces backpressure, allowing the engine to breathe more freely and extract maximum power. The result is increased horsepower and torque, as well as improved engine responsiveness.

This axle-back configuration means that the system only replaces the exhaust from the catalytic converters (cat-back) to the rear tips, leaving the factory front exhaust system in place. This setup offers a perfect balance between performance and affordability, delivering significant power gains without the need for a full exhaust system replacement.

The system is constructed from premium 304 stainless steel, ensuring durability and resistance to corrosion. The polished finish of the exhaust tips adds a touch of elegance and sophistication to the vehicle's exterior.

Installing the Stillen Cat-Back Exhaust System is a straightforward process, thanks to the bolt-on design. The system comes with all necessary hardware, including exhaust clamps and mounting brackets, for a hassle-free installation experience.

In summary, the Stillen 504391 Axle-Back Cat-Back Exhaust System for Nissan Maxima models from 2016 to 2021 is an excellent choice for those seeking to enhance the performance and exhaust note of their vehicle. With its larger diameter, stainless steel construction, and bolt-on design, this system is a worthwhile investment for any Maxima enthusiast.

Stille 504391 Axle-Back Cat-Back Exhaust System for Nissan Maxima (2016-2021): A Comprehensive Analysis

The Stille 504391 axle-back cat-back exhaust system is a popular aftermarket upgrade for the Nissan Maxima (2016-2021) models. This system is known for its performance improvements and unique exhaust note. In this analysis, we will discuss the pros and cons of investing in the Stille 504391 system, followed by an Recommendation.

1. Performance Enhancement: The Stille 504391 axle-back cat-back exhaust system enhances the engine's performance by reducing backpressure, which improves the overall power output and throttle response.

2. Increased Horsepower and Torque: This exhaust system is designed to increase horsepower and torque, providing a noticeable improvement in acceleration and overall driving experience.

3. Unique Exhaust Note: The Stille system offers a more aggressive and sporty exhaust note, giving your Nissan Maxima a distinct and appealing sound.

4. Improved Fuel Efficiency: Some users have reported improved fuel efficiency due to the reduced backpressure and improved airflow.

5. Durable Construction: The Stille exhaust system is constructed of high-quality stainless steel, ensuring it is rust-resistant and long-lasting.

6. Easy Installation: The system comes with all necessary hardware and instructions, making it relatively easy for an experienced DIY enthusiast to install.

1. Cost: The Stille 504391 axle-back cat-back exhaust system is a premium aftermarket part, and the cost may be prohibitive for some buyers.

2. Loud Exhaust Note: The exhaust system may be too loud for some users, especially those who prefer a quieter driving experience. It is recommended to check local noise regulations before installing.

3. Possible Check Engine Light: In some cases, installing an aftermarket exhaust system may cause the check engine light to illuminate. This is typically due to the O2 sensors not being able to read the new exhaust gases properly. However, this issue can be resolved with the use of compatible O2 sensor adapters or replacing the O2 sensors.

The Stille 504391 axle-back cat-back exhaust system offers significant performance improvements, unique exhaust note, and a distinct appearance for the Nissan Maxima (2016-2021) models. While the cost may be a concern for some buyers, the benefits of increased horsepower, torque, and fuel efficiency, along with the durability of the system, make it a worthwhile investment for those seeking a more engaging driving experience.

If you are looking to enhance the performance, sound, and appearance of your Nissan Maxima (2016-2021), and have the budget for it, the Stille 504391 axle-back cat-back exhaust system is an excellent choice. Just make sure to consider the potential for increased noise level and the possibility of a check engine light, and take the necessary steps to address these concerns if they arise.

part # 504391 prices

• $791.60-$811.21

specifications frazzlekits:

• for models: Maxima
• for makes: Nissan
• for years: 2016-2021
• brand: Stillen
• type: Exhaust Systems
• manufacturer part number: 504391
• manufacturer warranty: Yes

shipping frazzlekits:

• transit: 9-15 Days
• cost: $0.00
• type: Fixed
• class: Standard
• service: Standard

offer frazzlekits:

• options: Ship-to-home
• quantity: 2
• sold: 0
• started: May 27, 2026
• availability: In Stock

seller frazzlekits:

• rating: 99.9%
• # reviews: 132171

general frazzlekits:

• condition: New
• Car Truck Parts Accessories > Exhaust Emission Systems > Exhaust System Kits

returns frazzlekits:

• policy: Returns Accepted
• time: 30 Days
• paid by: Seller

payments frazzlekits:

• wallet: Apple-pay
• credit card: Mastercard
• other

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