New Complete Pair GM GMC Chevrolet 6.6L OHV Duramax Diesel LML Cylinder Heads 2011-2016 | No Core Required

Brand New · Not Remanufactured · In Stock Complete Pair — 6.6L LML Duramax Cylinder Heads · 2011–2016 These are brand-new high-density aluminum — not rebuilt cores of unknown history. Every pair is precision-machined in-house on Rottler equipment, pressure tested to 60 PSI, vacuum tested port-by-port, and assembled in a clean environment before it ships. The result is a drop-in replacement engineered to handle the LML’s demanding cylinder pressures and thermal loads right out of the box. ��️ 2-Year Unlimited Mileage Warranty �� Pressure Tested to 60 PSI �� In-House Precision Machined �� Ships UPS Ground — Lower 48 ↩️ No Upfront Core Fee Technical Specifications Engine Displacement 6.6L Duramax Diesel Engine Code LML Valve Train OHV (Overhead Valve) Condition ✓ Brand New — Not Remanufactured Year Range 2011 · 2012 · 2013 · 2014 · 2015 · 2016 Quantity Complete Pair — Driver & Passenger Included Valves & Springs Pre-Installed Gasket Surface Pre-milled & MLS gasket verified Pressure Test 60 PSI — Exceeds Factory Standard Warranty 2-Year Unlimited Mileage Shipping UPS Ground — Lower 48 States Our In-House Machining Process Every head runs through our full in-house process — not just pulled off a shelf and shipped. Step 01 Chemical Clean & Debris Removal Every casting is chemically cleaned and blown out — removing oils, shavings, and debris so your oiling system stays uncontaminated from first start. Step 02 Guide Sizing & Valve Seat Cutting Final guide sizing and precision multi-angle valve seat cutting on Rottler equipment — perfect geometry and clearances before anything goes to the assembly bench. Step 03 Pressure Tested to 60 PSI We go beyond the factory standard. Every head is verified at 60 PSI to confirm zero porosity leaks or internal defects that could compromise cooling or oiling. Step 04 Dimensional Inspection Multi-point gasket surface and bore alignment inspection. Perfectly flat within OEM tolerances — critical for a proper MLS head gasket seal. Step 05 Clean-Room Assembly Valvetrain components installed in a controlled environment. Spring heights and seal seating verified — balanced and ready for high-performance use. Step 06 Vacuum Seal Verification Every intake and exhaust port is vacuum tested for a 100% airtight valve-to-seat seal — maximum compression and peak performance from day one. Vehicle Fitment Fits all 2011–2016 GM trucks and vans equipped with the 6.6L Turbo Diesel LML engine code. Chevy Silverado 2500 HD 2011–2016 · 6.6L LML Chevy Silverado 3500 HD 2011–2016 · 6.6L LML GMC Sierra 2500 HD 2011–2016 · 6.6L LML GMC Sierra 3500 HD 2011–2016 · 6.6L LML GMC Sierra Denali 2500 2011–2016 · 6.6L LML GMC Sierra Denali 3500 2011–2016 · 6.6L LML Chevy Express 2500 Van 2011–2016 · 6.6L LML Chevy Express 3500 Van 2011–2016 · 6.6L LML GMC Savana 2500 Van 2011–2016 · 6.6L LML GMC Savana 3500 Van 2011–2016 · 6.6L LML ▼  Full Year-by-Year Fitment List 10 Models · 60 Fitments Vehicle Model Years Chevrolet Silverado 2500 HD 6.6L Turbo Diesel LML 201120122013201420152016 Chevrolet Silverado 3500 HD 6.6L Turbo Diesel LML 201120122013201420152016 GMC Sierra 2500 HD 6.6L Turbo Diesel LML 201120122013201420152016 GMC Sierra 3500 HD 6.6L Turbo Diesel LML 201120122013201420152016 GMC Sierra Denali 2500 6.6L Turbo Diesel LML 201120122013201420152016 GMC Sierra Denali 3500 6.6L Turbo Diesel LML 201120122013201420152016 Chevrolet Express 2500 Van 6.6L Turbo Diesel LML 201120122013201420152016 Chevrolet Express 3500 Van 6.6L Turbo Diesel LML 201120122013201420152016 GMC Savana 2500 Van 6.6L Turbo Diesel LML 201120122013201420152016 GMC Savana 3500 Van 6.6L Turbo Diesel LML 201120122013201420152016 All vehicles require 6.6L Turbo Diesel · LML engine code  ·  Not sure? Call 727-609-1700 Warranty & Core Return ��️ 2-Year Unlimited Mileage No mileage caps. No fine-print traps. If a covered defect arises, we make it right — period. View Full Warranty → ↩️ No Core required No core required on these cylinder heads. View Core Policy → Why Heavy Duty Parts Company? The LML Duramax demands precision. A sloppy head job means repeat gasket failures, coolant in the combustion chamber, and oil contamination. Our heads are brand-new castings machined in-house, tested to 60 PSI, and verified before they leave the building. This isn’t shelf stock — it’s a part we’d put on our own truck. Fits 2011–2016 Chevy Silverado 2500HD & 3500HD, GMC Sierra 2500HD & 3500HD, Sierra Denali 2500 & 3500, Chevy Express 2500 & 3500 vans, and GMC Savana 2500 & 3500 vans — all with the 6.6L LML engine. �� Call 727-609-1700 Mon–Fri · 8AM–5PM Eastern · We Know Duramax