Hennessey transformed the GMC Sierra AT4 into a 700-horsepower off-road monster built to challenge Ford’s fiercest trucks.
In recent years, General Motors has largely stayed out of the super-truck wars, leaving the spotlight to the Ford Raptor R and RAM TRX. But nature abhors a vacuum, and Texas-based Hennessey Performance decided to step in on GM’s behalf. Starting with a standard GMC Sierra AT4, the tuner created a high-performance beast known as the Goliath 700.
The first order of business was replacing the truck’s factory 3.0-liter turbo-diesel inline-six with GMC’s 6.2-liter V8, which Hennessey then equipped with a supercharger. The result is an impressive 700 horsepower and 611 lb-ft of torque.
That kind of output gives the full-size pickup sports-car levels of acceleration, allowing it to sprint from 0 to 62 mph in just 4.2 seconds. But turning the Sierra into a straight-line drag machine wasn’t enough. Hennessey also reworked the truck’s suspension to improve its off-road credentials.
The factory rear springs and shocks were replaced with a BDS suspension system featuring reinforced upper control arms. At the same time, the tuner retained the excellent Multimatic DSSV adaptive dampers, which were already more than capable. Finishing off the package are 20-inch wheels wrapped in massive 35-inch mud-terrain tires.
The Goliath’s appearance leaves no doubt about its intentions. The stock bodywork gives way to heavy-duty steel front and rear bumpers designed to protect both the wheels and radiator. For nighttime adventures, Hennessey added a 40-inch LED light bar along with a pair of 3-inch auxiliary fog lights.
Additional visual upgrades include carbon-fiber trim on the tailgate, aggressive badging, and power-retractable side steps that tuck away while driving. Inside, the upgrades are more subtle, featuring branded floor mats, embroidered headrests, and a numbered plaque identifying each individual build.
Every Goliath 700 undergoes dyno testing before delivery and is backed by a limited warranty covering three years or 62,000 miles.
GM may never have delivered a factory-built rival to the RAM TRX, but the Hennessey Goliath 700 proves that a serious answer to Ford’s Raptors can still come from the aftermarket. All it takes is the right vision—and a few extra dollars in the bank.