CUMMINS ISX15 | X15 CHROME EXHAUST MANIFOLD

If you’re looking to improve the performance and durability of your Cummins ISX15 or X15, the PDI Big Boss Exhaust Manifold is engineered to deliver better airflow, cooler exhaust temperatures, and improved turbo response.

PDI designed this manifold to maximize exhaust airflow, helping reduce turbo lag and allowing the turbocharger to spool more efficiently. During development, each runner was carefully analyzed and tested to ensure balanced airflow into the turbo, improving overall engine efficiency.

Compared to a factory manifold, the PDI Big Boss design increases airflow by up to 20%, while lowering exhaust gas temperatures by as much as 75–100°F. Improved airflow and optimized exhaust pressure-to-boost pressure ratios can also help support better engine performance and potential fuel economy improvements.

PDI manufactures these manifolds using High Silicon with Molybdenum Ductile Iron (HSMD), a premium material designed to withstand extreme heat cycles. This superior construction helps eliminate common failures such as warping, cracking, and heat-related fatigue that can occur with stock manifolds over time.

Available For

Cummins ISX15 & X15 Engines (2010–2020)

Key Benefits

• Up to 20% increase in airflow over stock manifolds

• 75–100°F cooler exhaust gas temperatures

• Helps reduce turbo lag and improve turbo response

• Maintains optimal exhaust pressure to boost pressure ratios

• Potential for improved fuel efficiency and engine performance

• Made in the USA

Premium Construction

• Built from High Silicon Molybdenum Ductile Iron (HSMD)

• Designed to resist warping, cracking, and heat erosion

• Reinforced mounting surfaces for long-term durability

Warranty

3 Year Unlimited Mileage Warranty

At Redneck Diesel Performance, we carry parts that help your truck run cooler, spool faster, and stay reliable mile after mile. And if you’d rather have it done professionally, we can install the manifold for you at our shop as well.

For more information or help with your setup, call us at 972-921-4316.