Known under the VIN code Y, the L5P Duramax is the latest evolution of the 6.6-liter turbo diesel that powers the Silverado HD and Sierra HD. Introduced for the 2017 model year and mated exclusively ...
If you own a 2017–2025 Chevy Silverado or GMC Sierra HD with the 6.6L L5P Duramax, you already know it’s a powerhouse—445 hp and 910 lb-ft from the factory. But even this engine has limits, and most ...