2025 GMC Sierra 2500HD Diesel

GMC's 2025 Sierra 2500HD is the middle man between the capable but consumer-grade Sierra 1500 and the house-hauling Sierra 3500, made for moving the heaviest loads. The 2500 is an amply capable workhorse that's able to tow up to 22,390 pounds and haul more than 4,000 pounds in its bed. It falls a little short of some competitors in these metrics, but not by enough to be a deal-breaker if you like the Sierra's other strengths.

The Sierra 2500's 2024 refresh brought it much closer to its main rivals in terms of output, towing and hauling. Those rivals, of course, are the Ram 2500, which is a superb near-luxury competitor, and the Ford F-250 Super Duty. The Ford is the most recently redesigned truck in the segment, undergoing its last overhaul for 2023, while the Ram was last all-new in 2019. There's also the mechanically identical Chevrolet Silverado 2500, which costs slightly less and offers less luxurious upper trims.

The AT4 and AT4X trims aren't new to the Sierra 2500 lineup this year, but we've not discussed them here in detail before. Both come standard with four-wheel drive. As the off-road-oriented trim, the AT4 gets twin-tube Rancho shocks, which offer more damping control than conventional monotube shocks. The AT4 also adds hill descent control and skid plates. Step up to the AT4X and you'll get an additional 1.5 inches of suspension lift and Multimatic spool-valve dampers, which give even more damping control and greater durability. A driver-selectable locking rear differential and 18-inch mud-terrain tires are also included. Finally, there's the AEV Edition package, which can be added to the AT4X. It adds steel bumpers from American Expedition Vehicles as well as unique wheels and stamped-steel skid plates.