Hennessey Turns GMC’s Sierra AT4 Into A 700-HP Answer To The Raptor

Texas tuner Hennessey has unleashed its latest beast—a supercharged GMC Sierra AT4 packing 700 horsepower, dubbed the Goliath 700 package.

The move comes as GMC itself skipped the high-performance off-road pickup battle, leaving the door wide open for aftermarket specialists to step in.

Hennessey replaces the Sierra AT4’s stock 3.0-liter turbo-diesel inline-six with a supercharged 6.2-liter V8, transforming it into a fire-breathing off-roader that rivals the Ford F-150 Raptor R and Ram 1500 TRX.

The heart of the beast is a massive supercharger bolted onto the 6.2-liter V8, pushing output to 700 hp at 5,500 rpm and 611 lb-ft (828 Nm) of torque at 4,200 rpm. That’s enough grunt to launch the truck from 0-60 mph in just 4.2 seconds. The package isn’t just about straight-line speed, though.

Hennessey bolsters the Sierra AT4’s off-road chops with a suite of upgrades, including an air-to-water intercooler, a stainless-steel catback exhaust with black tips, and Multimatic DSSV shocks.

The suspension gets a serious overhaul with upgraded DBS components and new upper control arms, while the wheels roll on 20-inch rims wrapped in 35-inch off-road tires.

The truck’s rugged credentials are further enhanced with new steel front and rear bumpers, a 40-inch LED light bar, three-inch LED pod lights, carbon fiber tailgate accents, electronic power running boards, and a Hennessey skid plate.

Inside, the Goliath 700 package adds all-weather floor mats, numbered plaques, and embroidered headrests. Every Hennessey conversion comes backed by a three-year / 36,000-mile limited warranty.

With its Goliath 700 package, Hennessey has effectively filled the gap left by GMC, delivering a Sierra AT4 that’s as capable on the trail as it is on the street.