PDI Big Boss CAT 3406E/C15/C16 Stage 2 Cylinder Head

Engineered for Strength. Designed for Durability. Built for Higher Performance.

The PDI Big Boss™ Stage 2 Cylinder Head builds upon our Stage 1 design with the addition of precision stainless steel firewiring for enhanced head gasket retention in demanding Caterpillar diesel engine applications.

Featuring an engineered metallurgical composition, premium Inconel intake and exhaust valves, improved cooling passages, and precision-installed stainless steel firewire, the Big Boss™ Stage 2 Cylinder Head is designed for the extreme temperatures, thermal cycling, and continuous operating demands of heavy-duty diesel engines.

Precision Stainless Steel Firewiring | Ships Fully Assembled | No Core Deposit Required

Features & Benefits

Precision Stainless Steel Firewiring — Enhanced Head Gasket Retention

The PDI Big Boss™ Stage 2 Cylinder Head features precision-machined grooves in the cylinder head's fire deck, fitted with stainless steel firewire. Positioned outside the head gasket's primary combustion seal, the firewire creates an additional point of contact that bites into the head gasket when properly installed.

This design provides additional mechanical locking engagement between the cylinder head and head gasket, helping to resist gasket movement and support sealing integrity under demanding engine operating conditions including todays increased cylinder pressures.

Engineered Metallurgical Composition

A specialized alloy formulation designed to withstand the extreme heat and demanding conditions of heavy-duty diesel applications. The carefully engineered material composition promotes structural integrity, thermal stability, and long-term casting durability.

Premium Inconel Intake & Exhaust Valves

Equipped with high-temperature-resistant Inconel intake and exhaust valves, engineered for strength and durability in demanding operating conditions.

Advanced Cooling Passage Design

Improved internal cooling passages are designed to support efficient heat transfer and improved thermal management throughout the cylinder head.

Fully Assembled — Ready for Installation

Each PDI Big Boss™ Stage 2 Cylinder Head ships fully assembled, eliminating the need to purchase and assemble individual valvetrain components separately.

No Core Deposit Required

Purchase your new PDI Big Boss™ Cylinder Head without an additional core deposit or the requirement to return your old cylinder head. No core return process, no waiting for a core refund, and no additional core deposit added to your purchase.

Performance-Focused Construction

Engineered with premium materials, precision stainless steel firewiring, and design features intended to support structural integrity and durability under demanding engine operating conditions.

Engine Compatibility

Designed for select Caterpillar 3406E, C15, C16 and C18 diesel engines.

Common Engine Serial Prefixes:
5EK, 6TS, 1LW, 2WS, 6NZ, MBN, BXS, MXS, NXS, SDP, 1MM, 7CZ

Our sales team will contact you to confirm fitment before shipment!

Caterpillar OEM Cross-Reference Numbers

OEM part numbers are provided for cross-reference purposes only. Engine serial number verification is required to confirm compatibility.

Why Choose a PDI Big Boss™ Stage 2 Cylinder Head?

The cylinder head is one of the most critical components in any heavy-duty diesel engine. Extreme combustion temperatures, repeated thermal cycling, and sustained engine loads place tremendous stress on conventional cylinder head castings and valvetrain components.

The PDI Big Boss™ Stage 2 Cylinder Head combines the premium construction of our Stage 1 design with precision stainless steel firewiring. This additional mechanical engagement with the head gasket is designed to help resist gasket movement and support sealing integrity under demanding engine operating conditions.

With a fully assembled design, no core deposit requirement, and premium manufacturing, PDI delivers a straightforward cylinder head replacement solution without compromising on quality.

Warranty & Support

2-Year, Unlimited-Mileage Limited Warranty

Backed by PDI's commitment to product quality and customer support.

For fitment verification or technical assistance, contact PDI at 800-511-1231.