Fleece Freedom Series HD Cylinder Head – 18mm dowel (FPE-61-10011-HD) for 2003-2007 PowerStroke 6.0L

Fleece Performance Freedom Series HD Cylinder Heads for 2003–2007 6.0L Power Stroke

Fleece Performance builds Freedom Series HD cylinder heads specifically for the 2003–2007 6.0L Power Stroke because durability and reliability matter. Instead of reusing factory castings, Fleece starts with a brand-new, higher-strength alloy design, which improves longevity and reduces failure under heavy load. Additionally, the single-piece O-ring sealing system eliminates combustion leaks that commonly occur with traditional wire designs. As a result, these fully assembled cylinder heads provide consistent performance for daily driving and demanding towing applications.

The Fleece Performance Freedom Series HD cylinder heads are engineered specifically for the 2003–2007 Ford 6.0L Power Stroke, delivering unmatched durability, sealing performance, and long-term reliability. Manufactured in Fleece Performance’s state-of-the-art Freedom Racing Engine facility, each cylinder head is built to meet or exceed factory specifications while addressing the known weaknesses of OEM castings.

Unlike remanufactured or reused OE castings, these HD cylinder heads start with a brand-new, higher tensile strength casting, engineered from the ground up with increased material thickness and structural reinforcement in critical areas. The result is a stronger, longer-lasting cylinder head designed for daily driving, heavy towing, and demanding work applications where uptime matters most.

Each cylinder head comes from Fleece Performance’s state-of-the-art Freedom Racing Engine shop and meets or exceeds factory specifications. Every head is also equipped with Fleece Performance’s exclusive single-piece O-ring combustion sealing system, providing superior sealing compared to traditional seamed stainless wire designs.

Key Features

• Brand-new, higher tensile strength cylinder head casting

• Race-proven design engineered for durability and longevity

• Hardened, oversized American-made press-in valve seats

• Fleece Performance exclusive single-piece hoop-style O-ring for superior combustion sealing

• Complete new valvetrain including stainless steel and Inconel alloy valves

• Fully assembled and ready to install

• No core charge and no core return required

What Sets Fleece Performance Cylinder Heads Apart

Improved Casting Design

These are not recycled or lightly revised OE castings. Fleece Performance cylinder heads are engineered from the ground up using a higher-strength alloy with added wall thickness and reinforcement in high-stress areas. Years of real-world testing and development ensure exceptional durability and resistance to cracking.

Extreme-Duty Valve Seats

The American-made valve seats are produced from a tungsten alloy, offering significantly higher hardness and wear resistance than OEM replacements. This race-proven design improves long-term stability and reliability under high temperatures and heavy loads.

Exclusive Single-Piece O-Ring Sealing

Fleece Performance is the only manufacturer offering a single-piece hoop-style O-ring for the 6.0L Power Stroke. Unlike traditional stainless wire O-rings that rely on a seam, this one-piece design delivers consistent, complete combustion sealing for improved head gasket reliability.

Application Notes

• All 20mm dowel cylinder heads are configured for 2-bolt rocker box applications

• Fleece Performance recommends using 6.4L Power Stroke pushrods (Ford Part No. 8C3Z-6565-B)

  • 6.4L pushrods are 0.050” shorter than 6.0L pushrods and help accommodate tolerance stack-ups commonly encountered during cylinder head replacement

• Head gasket not included

  • Recommended head gasket: Ford Part No. KZ3Z-6051-B

Cylinder Head Identification and Selection

To ensure proper fitment, select the correct cylinder head using the engine serial number. The serial number is located on the rear driver’s side of the engine block. On vehicles with the original Fuel Injector Control Module (FICM), the serial number may also be found on the identification sticker on top of the FICM. If FICM originality is uncertain, always reference the serial number on the engine block.

Installation Instructions for the Freedom Series 6.0 Power Stroke cylinder heads