2021 Sierra 2500 L5P 6.6 Duramax Engine & Transmission 18k Miles

L5P Duramax Engine for Sale

This L5P Duramax engine and transmission comes from a 2021 GMC Sierra 2500 with only 18k miles, giving you GM’s most powerful Duramax and its matching Allison automatic.

2021 GMC Sierra 2500 L5P 6.6L Duramax Engine & Transmission – 18K Miles
This 2021 GMC Sierra 2500 powertrain package features the 6.6L L5P Duramax turbo-diesel V8 paired with its compatible transmission. Designed for heavy-duty truck applications, the L5P delivers substantial torque and towing capability, making it suitable for demanding work and compatible replacement projects.
The package is listed with approximately 18,000 miles. The reported mileage and exact components should be verified before purchase, particularly when installing the powertrain in a different truck.
Compatible GMC Applications
GMC Sierra 2500HD with matching L5P specifications
GMC Sierra 3500HD, subject to configuration compatibility
Compatible GMC heavy-duty truck replacement projects
Compatible Chevrolet Applications
Chevrolet Silverado 2500HD with matching L5P specifications
Chevrolet Silverado 3500HD, subject to configuration compatibility
Compatible Chevrolet heavy-duty diesel truck projects
Popular Custom Applications
GMC Sierra and Chevrolet Silverado diesel restorations
Heavy-duty work truck replacements
Compatible towing and hauling truck builds
Specialized diesel performance projects
Custom heavy-duty truck builds
Engine and Transmission Highlights
Engine:
GM 6.6L L5P Duramax turbo-diesel V8
Model year:
2021
Mileage:
Approximately 18,000 miles, as listed
Original application:
GMC Sierra 2500HD
Fuel type:
Diesel
Transmission:
Included; exact model and configuration should be confirmed
Ideal for:
Compatible heavy-duty truck replacements and diesel projects

About the L5P Duramax Engine & Transmission

The L5P is the fifth generation of GM’s 6.6L Duramax turbo diesel, introduced for the 2017 model year in Silverado HD and Sierra HD trucks. It features a stronger block, revised heads and a variable-geometry turbocharger, and it is rated at up to 445 horsepower and 910 lb-ft of torque in later model years. The Allison ten-speed automatic used in 2020 and newer trucks is designed to handle that torque while towing heavy loads.

With low mileage, this L5P Duramax engine and transmission package is an excellent option for replacing a damaged drivetrain or for a high-end diesel swap.

What to Confirm

• Your truck’s model year and whether the transmission is the Allison 10-speed or earlier 6-speed.
• ECU and TCM programming requirements for your VIN.
• Emissions equipment (DPF, SCR and DEF system) needed in your region.

Installation Tips

Change engine oil, coolant and transmission fluid, inspect the turbo and replace any damaged sensor connectors before startup. Have a GM dealer or qualified diesel shop handle programming.

FAQ

Do you export the L5P Duramax engine and transmission? Yes, we ship to the USA and overseas.

Buying Your L5P Duramax Engine from Auto Parts Export

Auto Parts Export is a Canadian supplier of used engines, transmissions and OEM replacement parts. Browse more Engine & Transmission Packages, or use our part finder if you need something specific. We ship across Canada and overseas, so read about shipping and international shipping, and review our warranty and returns policy before you order. For official model and specification information, visit the GMC website.

How Ordering Works

Send us your VIN, engine code or part number and our team will check that the L5P Duramax Engine matches your vehicle. We can share additional photos and any details we have on the unit, then provide a written quote that includes freight to your address, terminal or port. Large items such as engines and transmissions normally travel by freight on a pallet or in a crate, and we will explain the packaging, carrier and timing before you pay so there are no surprises when your order arrives.

Ready to order the L5P Duramax Engine? Contact Auto Parts Export for pricing, extra photos and a shipping quote.

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