The L5P isn't like the LML or the LBZ. GM locked it down harder than any previous Duramax — military-grade ECM encryption, tighter emissions hardware integration, and a sensor network that will brick ...
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 ...