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2023 GM Duramax 2500HD–3500HD Diesel Engine 6.6L

2023 Duramax 6.6L Diesel Engine

Used Engines Inventory

Reman Engines Inventory

Diesel Engines Inventory

Latest-generation L5P long block option

The 2012 Ford Powerstroke 6.7L Diesel Engine is a robust choice for heavy-duty applications, found in the 2012 Ford F250, F350, and F550 models. This turbocharged V8 engine delivers significant torque and horsepower, making it ideal for towing and hauling. Its design ensures both performance and efficiency, with a reputation for reliability and durability. Whether for work or recreation, the 6.7L Powerstroke handles demanding tasks with ease. For more details on its performance and specs, visit our 2012 F250 diesel engine page.

Diesel Engine

Latest-generation L5P long block option

The 2023 Duramax 6.6L L5P long block delivers exceptional power, refined fuel delivery, and advanced emissions performance for GM HD diesel engine platforms. Houston Engines provides both reman and tested used L5P engine options engineered for towing and commercial-duty usage. Each block is inspected for cracks, machined for accurate sealing, and verified for lubrication consistency. Cylinder heads are pressure-tested and rebuilt with new valve guides and seals. Updated pistons, rings, and bearings restore compression and long-term durability. This remanufactured engine ensures dependable output and service life for Silverado 2500 engine and Sierra 3500 engine applications.

Reman engines undergo complete machining including torque-plate honing, deck resurfacing, crankshaft reconditioning, and rotating assembly balancing to restore factory-level precision.

Cylinder heads receive full reconditioning with new valve components to maintain consistent airflow and sealing. Updated gaskets, seals, and bearings help restore combustion stability and prevent heat cycling issues common in heavy-duty diesel engine usage. These reman units are built to maintain long-term Duramax reliability while delivering smooth operation under sustained load.

Used L5P engines must pass compression testing, leak-down diagnostics, and internal cylinder inspection via borescope to verify structural integrity. External sealing components receive updates, and accessories are evaluated for compatibility to ensure proper installation. Houston Engines ensures both reman 6.6L Duramax and used L5P engine options deliver OEM-level performance, stable towing characteristics, and long-term durability across GM HD diesel engine applications, giving operators dependable power whether for work, fleet service, or everyday driving.

Gas Engines | Diesel Engines | Hybrid Engines

Save With Our Large Inventory of Used Engines

Are you in the market for a used engine to get your vehicle back up and running? Look no further than Houston Engines. We offer a wide selection of high-quality, used engines at affordable prices. We pride ourselves on our commitment to customer satisfaction and provide a hassle-free shopping experience for all our clients.

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Gas Engines

Diesel Engines

Hybrid Engines

Engine Testing Procedures and Warranty Coverage

Every long block undergoes compression matching, oil pressure verification, and cylinder balance evaluation. When applicable, hot-run testing is documented and stored under the engine’s serial record for warranty and service reference. These procedures ensure system integrity prior to installation.

Reman engines include enhanced GM diesel warranty coverage for added reliability assurance. Used engines include a standard limited warranty that requires proper installation documentation and maintenance validation.

Prime the oiling system and use break-in oil during the early operating period to ensure proper lubrication.

Replace coolant, filters, belts, and hoses so all supporting systems remain clean and free of contamination. Inspect the EGR, turbocharger, and intercooler for debris or residues from previous engine failures, preventing potential damage and supporting optimal 6.6L L5P performance.

Warm the engine gradually, monitor oil pressure and temperature, and avoid heavy loads until the break-in process is complete. Following proper installation and 6.6L break-in procedures helps maintain Duramax reliability, towing stability, and warranty compliance for the 2023 Duramax 6.6L L5P. Adhering to these steps ensures long-term performance, protects engine components, and keeps your GM HD truck running at peak efficiency under heavy-duty conditions.

Engine Fitment and Vehicle Compatibility Guide

Fits 2023 Chevrolet Silverado and GMC Sierra 2500HD/3500HD trucks equipped with the 6.6L L5P Duramax platform. Verify VIN, emissions calibration, and transmission pairing before ordering to ensure correct fitment for your Silverado 2500 engine or Sierra 3500 engine requirements.

Houston Engines confirms casting match, accessory pattern alignment, and required configuration details to ensure a smooth installation of your remanufactured engine or used engine.

Contact Houston Engines for installation steps, torque specifications, freight arrangements, and GM diesel warranty activation. Our technical support team ensures proper setup, guiding you through each step for reliable performance. With expert assistance, your GM diesel engine achieves long-term durability, smooth operation, and dependable results, giving both daily drivers and commercial operators confidence in every installation.

Freight process and core return

Duramax long blocks ship on reinforced pallets with corner guards, protective wrapping, and steel banding to prevent movement during transportation. Lift-gate or dock delivery services are available nationwide, ensuring secure L5P freight handling and safe arrival at your location. Proper packaging protects the engine from damage during transit.

Cores must be drained and returned inside the original crate using the included RMA and shipping documentation. Secure the engine within the crate to avoid shifting or tipping during return transit. Following these steps ensures the engine arrives safely for inspection and evaluation.

Final inspection determines the eligibility of your core credit. Missing components, internal damage, or contamination can reduce the credit value. Carefully review the core checklist to ensure maximum refund and a smooth, hassle-free return process.

Frequently Asked Questions (FAQs)

Frequently Asked Questions (FAQ)

What trucks use the 2023 Duramax 6.6L L5P?

It fits 2023 Chevrolet Silverado 2500HD/3500HD and GMC Sierra 2500HD/3500HD trucks.

Do you offer both reman and used engines?

Reman engines are rebuilt to factory standards with new components, while used engines are inspected, resealed, and tested to ensure reliability.

Are reman engines fully rebuilt?

Yes, they receive complete machining, reconditioning, and new internal components.

What testing do used engines undergo?

Compression, leak-down, borescope inspection, and external component evaluation.

Is warranty included?

Reman engines include enhanced warranty coverage; used units include standard limited warranty.

How long is the break-in period?

Accessories vary by build. Most long blocks include heads and blocks, while optional components can be added upon request.

Is this engine suitable for towing?

Yes, the 2023 L5P platform supports heavy towing and commercial operation.

Do you assist with installation?

Yes, contact us for torque values, steps, and technical support.

How does freight shipping work?

Engines ship on reinforced pallets with protective packaging for safe delivery.

Is a core return required?

Yes, and returning it with all components ensures maximum credit.

Why Buy From Us?

We strive to be the ultimate destination for recycled auto parts. With access to a vast inventory and exclusive parts network, we offer millions of quality parts. We specialize in used engines and transmissions with new stock weekly. Our commitment to quality means that you can trust that you're getting the best possible part for your vehicle.