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 ...

For decades now, the big three American automakers have been engaged in a game of one-upmanship over which company can fit the most powerful and torquiest diesel engines in their trucks. And, just as ...