Industrial Injection PDM-LLYRH GM Race Cylinder Heads — 2004.5–2005 LLY 6.6L Duramax

Unlock top-end durability and airflow for your LLY Duramax build with Industrial Injection’s race-prepped cylinder heads. Built to handle aggressive tuning, larger injectors, and sustained boost, these heads are a proven upgrade for competition or high-performance street trucks.

Key Features

• Race-prepped LLY castings with performance valve work
• Enhanced airflow for improved spool and high-RPM power
• Ideal with studs, upgraded gaskets, and performance injectors
• Ready for serious towing, drag racing, or sled pull setups

Fitment

Fits: 2004.5–2005 GM/Chevy 2500HD/3500HD with LLY 6.6L Duramax (VIN Code 2).

Shop more LLY 2004.5–2005 parts

What’s Included

• (1) Pair of Industrial Injection PDM-LLYRH race cylinder heads
• Pre-installed valve guides & seats (as supplied by manufacturer)

Recommended Supporting Upgrades

• ARP Head Stud Kit (Duramax)
• Duramax Head Gaskets (LLY thickness options)
• Injector Install/Seal Kits
• Cooling System Upgrades (radiator, thermostats)
• Industrial Injection Category

Installation Notes

• Professional installation recommended; verify surface finish and clean block decks.
• Use new head gaskets and torque fasteners per OEM/ARP instructions.
• Retune after install to take advantage of increased airflow.

FAQ

Q: Will these heads work on LB7, LBZ, or LMM?
A: No. These are built for the LLY 6.6L (2004.5–2005). For other generations, see our Duramax category.

Q: Do I need head studs?
A: Highly recommended for reliability under boost. See ARP Duramax studs.

Q: Are these ready to bolt on?
A: They arrive assembled as provided by Industrial Injection. Always inspect clearances and follow correct torque/sequence during install.

Specifications

Warranty & Returns

Manufacturer’s warranty applies. Core and restocking policies may apply where relevant. For details, contact our team before purchase.