Imagine driving a brand new Duramax with twice the factory horsepower. Obviously, your rig wouldn’t roll out of GM like that, but that doesn’t mean you couldn’t build it yourself. Thanks to a host of high quality, well-refined products being offered throughout the diesel aftermarket, it’s not hard to get a 2011-2015 LML Duramax-powered truck up to speed in a hurry. We recently sat in on a start-to-finish build at Randall’s Performance in Gladstone, Illinois, where a ’15 GMC Sierra Denali 2500 HD was fitted with some of most reputable power adders in the industry.
The weeklong build took the bone-stock, 3,500-mile GMC from 350 hp at the wheels to a tire shredding 700-plus. Key upgrades included: a compound turbocharger arrangement, CP3 conversion, injector up sizing, lift pump, and a built Allison transmission. Along the way—and despite more than doubling the truck’s original power output—crucial characteristics such as longevity, reliability, and drivability were in no way compromised. If you’re looking to turn your late model Duramax into the perfect truck, here’s some inspiration. DW
Randall’s Performance . 309.621.1099 . RandallsPerf.com