2017 GMC Sierra 2500 All Terrain X: Is this the Most Off-Road Capable Diesel HD Truck? (Cliffhanger 2.0)

2017 2018 gmc sierra 2500 hd all terrain x
GMC Sierra 2500 HD All Terrain X

The question is a simple one: is the 2017 GMC Sierra 2500 HD All Terrain X the most capable off-road heavy duty diesel-powered truck you can buy? We take on the Cliffhanger 2.0, our most difficult off-road test, to find out.

With the ability to tow 13,000-lbs and haul 2,200-lbs in this trim – the 2017 GMC Sierra 2500 All Terrain X is the whole package. Curious as to what you get with the All Terrain X package? It includes off-road tuned suspension with Rancho shocks, lots of skid plates, black painted wheels, Goodyear Wrangler Duratrac tires, side steps, a sports bar with LED lights, and special interior trim.

The part that matters to folks who like to go off-road is the beefy diesel, grippy tires and automatically locking rear diff. The big GMC has a massive heart. Its 445 horsepower 6.6-liter Duramax turbo-diesel V8 makes 910 lb-ft of torque. The power is dolled out through a six-speed Allison automatic transmission. The four-wheel drive system is conventional and it includes a 2-speed transfer case with low-range and a G80 automatic locking rear diff.

Curious about the 2017 GMC Sierra 2500 HD All Terrain X’s fuel efficiency and range? Click (here) to watch Roman drive across Utah and Colorado on a single tank of diesel.

We had a great time forcing this GMC Sierra 2500 All Terrain X beastie up Cliffhanger 2.0. It truly was a fun video to make. We aired down the tires for a little more grip, and we went up the more difficult “Dare” side of the trail. Try watching the video below and let’s see what you thought.

Nathan Adlen
Easily amused by anything with four wheels, Nathan Adlen reviews vehicles from the cheapest to the most prestigious. Wrecking yards, dealer lots, garages, racetracks, professional automotive testing and automotive journalism - Nathan has experienced a wide range of the automotive spectrum. Brought up in the California car culture and educated in theater, childhood education, film, journalism and history, Nathan now lives with his family in Denver, CO. His words, good humor and video are enjoyed worldwide.