★★★★★

Verified Google Reviews

★★★★★

Best prices and customer service on Duramax LML heads out there. Shipped fast and very cool about how long it took to get the cores back.

— Dan

★★★★★

Great company!! The heads arrived in great shape with all the parts. Very quick email responses to questions, comments, and concerns. One little issue with a few parts but was taken care of promply

— Randy Tinsley

★★★★★

Product was as described and packaged well! Communication throughout prosses was also great! I will definitely be using them in the future with other projects.

— Tommy Starogiannis

★★★★★

They supplied me with a perfect set of heads to bring my 1999 Ford Ranger back to life. Ranger Frank has been in the family since the day he rolled off the showroom floor. Its great to have him back on the road.

— Ron Long

“55565291 55573669 | New 1.4L DOHC Cylinder Head for Chevrolet Cruze, Trax, Sonic, Buick Encore – Heavy-Duty Aftermarket Casting” has been added to your cart. View cart

New Pair Chevrolet, GMC 6.6L Cylinder Heads for Sierra 2500 Pickup, Sierra 3500 Pickup, Silverado 2500 Pickup, Silverado 3500 Pickup (2004-2005)

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

Name: New Complete Pair GM GMC Chevrolet 6.6L OHV Duramax Diesel LML Cylinder Heads 2011-2016 | No Core Required
Brand: Heavy Duty Parts Company
SKU: CHEV110N
Price: 1395 USD
Availability: InStock

$1,395.00

2-Year

Warranty

Unlimited Mileage

Assembled

In USA

Florida-Based Shop

Quality

Tested

Pressure & Vacuum

Flat Rate

$49.99 Ship

No Surprises

500+ sold

✓ No Core Charge Required Up Front Return your old head after you receive yours — we send a prepaid label

⚙️ Upgrades & Add-Ons

🔍 Add Head Gasket Set +$495.00 Add Head Stud Kit

🔍 Add Head Stud Kit +$395.00

🛒 Your Selection

Total

Pay with Credit Card

Additional Info

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

Dedicated to Customer Satisfaction

What sets us apart from the competition is our dedication to customer satisfaction. We strive to make your shopping experience as seamless and convenient as possible. Our user-friendly online platform allows you to browse our comprehensive inventory, compare products, and place orders with ease. With secure payment options and swift shipping, you can trust that your order will arrive promptly, minimizing downtime and maximizing productivity.

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

Pay with Credit Card

Additional Info

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