2004.5-2005 LLY Duramax NEW Premium Stock Plus Cylinder Heads (RH & LH Set) - Industrial Injection - PDM-LLYSHN

2004.5-2005 LLY Duramax Premium Stock Plus New Cylinder Heads (RH and LH Set)
Restore factory performance and reliability to your 2004.5-2005 LLY Duramax 6.6L with these brand-new Premium Stock Plus cylinder heads. Designed as a direct replacement for factory heads, these new castings eliminate the uncertainty associated with remanufactured cores while delivering the durability, airflow, and performance required for stock and mild performance applications.
Each cylinder head is precision machined and assembled using premium components to ensure proper sealing, valvetrain stability, and long service life. Whether you're replacing damaged cylinder heads or building a fresh engine, these Premium Stock Plus heads provide a dependable foundation for your Duramax.
Key Features
Brand-new LLY Duramax cylinder head castings
Precision machined and assembled
Diamond honed valve guides
Unshrouded valves for improved airflow
High-strength, heat-treated iron-based valve guides
Premium nickel-based, non-magnetic valve seat inserts
Multi-angle valve job
New valve springs installed
Assembled and ready for installation
Direct replacement for factory cylinder heads
Ideal for stock replacement or mild performance builds
Premium Stock Plus Construction
Built from all-new castings, these Premium Stock Plus cylinder heads are engineered to provide exceptional reliability and performance. Each head undergoes precision machining and assembly processes to ensure consistent quality, proper sealing, and optimal airflow.
By starting with brand-new castings, these heads eliminate concerns associated with used cores, cracks, repairs, or previous heat cycles, providing a fresh foundation for long-term engine durability.
What's Included
Left and right new LLY cylinder heads
Fully assembled and ready to install
Not Included
Gaskets
Head bolts
Injectors
Installation hardware
Vehicle Fitment
2004.5-2005 GM Duramax LLY 6.6L
Chevrolet Silverado 2500HD
Chevrolet Silverado 3500HD
GMC Sierra 2500HD
GMC Sierra 3500HD
Why Choose These New LLY Cylinder Heads?
Brand-new castings with no core history
OE-style fit, function, and performance
Premium valvetrain and machining upgrades
Ideal for engine rebuilds and cylinder head replacement
Built for long-term durability and dependable operation
Core Return Information
Sold as a matched left and right pair.
To receive full core credit, a good, reusable pair of LLY cylinder heads must be returned. Cores must be free of cracks, excessive warping, or severe damage. Core returns are required within 90 days of purchase.