2024 GMC Sierra HD AT4X Diesel Takes On World’s Toughest Towing Test

The 2024 GMC Sierra HD AT4X Diesel is one of the toughest trucks on the market today. The standard Sierra 2500 is able to tow more than 10 tons while still being incredibly comfortable for all passengers. With the latest safety features and infotainment system, it’s excellent to travel for all journeys. Add in the AT4X trim and the Sierra HD becomes not just a towing machine, but also an off-road-able, heavy duty truck that can still be driven everyday. 

AT4X & AEV Edition

The AT4X off-road trim is new to the Sierra for 2024 and features multimatic DSSV dampers with a 1.5-inch suspension lift, rear e-locking differential, 25-inch Goodyear Territory tires, new and AT4X specific front upper and lower control arms plus steering knuckles, a larger steel transfer case skid plate and front aluminum skid plate, AT4X-only Obsidian Rush interior with massaging, full-grain leather-wrapped front seats, and a max towing capacity of 18,500 lbs. Adding the AEV Edition to the AT4X gives customers stamped steel bumpers with integrated recovery points with winch capability, heavy duty skid plates, special 18-inch Salta wheels, and exterior and interior AEV edition badging and cues. 

Ike Gauntlet Test

The Fast Lane Truck (TFLT) recently tested a Sierra HD AT4X AEV Edition on the Ike Gauntlet, an 8-mile stretch of I-70 that goes over the continental divide in the Colorado Rocky Mountains. It features a 7% grade with a peak elevation of 11,158 feet above sea level. With an 11,000 lb. trailer attached, they set off to go both up and downhill to test the capabilities of the AT4X AEV Edition 2500 HD. 

The Verdict

In testing at the Ike Gauntlet, the reviewers showed that with the cruise control set at 50 mph and the trailer and exhaust brakes turned on, the Sierra only needed to downshift once to maintain its speed going downhill, which is very impressive. Going uphill they were able to go from 35 mph to 60 mph in just 13.5 seconds while towing 11,000 lbs at 11,158 feet above sea level. They also felt as though the truck was incredibly comfortable, very nice and luxurious to drive, and perfectly powerful. They also recorded an average of 9.8 mpg over 183.6 miles with some idling, which, again, is very good when you think about towing thousands of feet above sea level where the air is very thin. 

Engine Choices

Buyers are able to choose between a 6.6-liter V8 gas engine that produces 401 horsepower and 464 lb-ft of torque with a 10-speed automatic transmission, or the legendary 6.6-liter Duramax V8 turbo-diesel that makes 470 horsepower and 975 lb-ft of torque with an Allison 10-speed automatic. In the case of the TFLT Ike Gauntlet test, they used a Duramax model. 

2024 Safety Features

For 2024, all models offer the Sierra HD Pro Safety package as standard. The safety features include: Forward Collision Alert, Lane Departure Warning, Automatic Emergency Braking, Front Pedestrian Braking, Intellibeam auto high beams, and Following Distance Indicator. As an available option, buyers can choose the Pro Safety Plus Package, which adds Rear Cross Traffic and Trailer Side Blind Zone Alert.

At Ewing Buick GMC, we take pride in offering the best vehicles to our customers. With hundreds of new and used vehicles to choose from, our amazing sales team and finance department will find you the right vehicle at the right price. Once you’ve purchased your vehicle, our stellar service department will ensure that your car stays in the best shape. We look forward to taking care of you in the future.