PDI Big Boss Stage 2 Performance Kit – Cummins X15 & ISX15 | SKU 7157728

PDI Big Boss Stage 2 Performance Kit – Cummins X15 & ISX15

The PDI Big Boss Stage 2 Performance Kit is the next level in Cummins X15 and ISX15 performance upgrades. Building upon the proven airflow improvements of the Stage 1 package, the Stage 2 Kit combines PDI's industry-leading intake, exhaust, and cooling technologies into one complete performance system designed to maximize efficiency, reliability, and horsepower potential.

Engineered specifically for owner-operators and fleets that demand more from their equipment, the Stage 2 package helps reduce turbo lag, improve throttle response, lower exhaust gas temperatures (EGTs), reduce oil temperatures, and improve overall engine efficiency under heavy loads.

Whether you're pulling heavy freight through mountain grades, operating in extreme climates, or looking to maximize engine longevity, the PDI Big Boss Stage 2 Performance Kit delivers one of the most comprehensive bolt-on upgrades available for Cummins ISX15 and X15 engines.

What's Included

• PDI Big Boss Intake Manifold
• PDI Big Boss Exhaust Manifold
• PDI Big Boss Dual Oil Cooler System
• Required hardware and installation components
• PDI engineered performance package designed to improve airflow and cooling efficiency

Key Features

• Complete airflow and cooling performance package
• Designed for Cummins ISX15 and X15 engines
• Improves intake airflow throughout the engine
• Improves exhaust flow to the turbocharger
• Reduces turbo lag and improves spool-up
• Lowers exhaust gas temperatures (EGTs)
• Reduces engine oil temperatures
• Improves throttle response and drivability
• Supports improved fuel economy
• Built for severe-duty commercial applications
• Made in the USA

Specifications

• Brand: PDI Performance Diesel
• Series: Big Boss™ Stage 2
• SKU: 7157728
• Application: Cummins X15 & ISX15
• Product Type: Performance Upgrade Package
• Installation: Direct Bolt-On Components
• Made In: USA

Applications

Compatible with Cummins X15 and ISX15 powered Peterbilt, Kenworth, Freightliner, Western Star, International, and Volvo trucks operating in long-haul, heavy-haul, vocational, and performance-focused applications.

Performance Benefits

• Improved intake airflow efficiency
• Improved exhaust flow and turbocharger performance
• Reduced turbo lag
• Lower exhaust gas temperatures
• Lower engine oil temperatures
• Enhanced engine reliability
• Improved throttle response
• Potential fuel economy improvements
• Better pulling power under load
• Reduced thermal stress on critical engine components

Why Upgrade to the Stage 2 Kit?

The Stage 2 Performance Kit addresses two of the biggest challenges facing modern heavy-duty diesel engines: airflow restriction and heat management. By combining upgraded intake and exhaust components with PDI's Dual Oil Cooler system, the Stage 2 package creates a more efficient engine environment that supports both performance and long-term reliability.

Lower operating temperatures and improved airflow help protect expensive engine components including turbochargers, pistons, bearings, cylinder heads, and valve train assemblies.

Why Choose PDI?

PDI Performance Diesel has spent decades engineering airflow and cooling solutions for the heavy-duty trucking industry. Their Big Boss product line is designed specifically to help diesel engines run cooler, breathe better, and perform more efficiently under demanding operating conditions.

Recommended Upgrades

• PDI Big Boss Turbocharger Upgrades
• High-Flow Air Intake Systems
• Premium Fuel Filtration Systems
• Performance Charge Air Coolers
• Heavy-Duty Cooling Components

Fitment Notice

Verify engine model and engine serial number (ESN) before ordering. Contact our team for application verification and product recommendations.