2025 GMC Sierra 2500HD Expert Review
Reviewed by Billy Rehbock
For when the Sierra 1500 doesn’t offer enough capability and the 3500HD is too much, the 2025 GMC Sierra 2500HD serves as a sort of heavy-duty middle ground. Most recently refreshed for the 2024 model year, the Sierra 2500HD receives further updates for 2025. Rivals include the Ford F-350 Super Duty, Ram 2500 Heavy Duty, and the Chevrolet Silverado 2500HD.
What’s New
- New 20-inch two-tone wheels
- Available Universal Vehicle Module
- Standard cruise control on all trims
- Standard trailer brake controller
- Front and Rear Park Assist added to 1SA Pro Safety Plus, Sierra HD Pro Safety Plus, and Fleet Convenience packages
- GMC logo added to back wall of spray-on bedliner
- Adaptive cruise control is now standard on AT4 and Denali
- Standard instrument panel 120-volt power outlet for SLE trim
- SLE trim receives a 120-volt bed-mounted power outlet and two USB ports
- MultiPro tailgate now available on SLE trim
- Three 20-inch wheel options discontinued
- Redwood Metallic paint discontinued
- Power take-off no longer offered on RWD models
- E85 FlexFuel capability no longer offered with regular cab
What We Think
Last year, GMC brought significant refinements to the Sierra 2500HD lineup, with changes including cosmetic enhancements, a new 10-speed automatic transmission for the gasoline V-8 engine option, increased horsepower and torque for the turbodiesel V-8, and more standard tech. The result is a dramatically improved heavy-duty truck with a strong suite of standard features.
The 2025 Sierra 2500HD is more refined than ever, with a quick-shifting gearbox equipped on all models. Gas trucks offer good daily drivability, and the diesel engine’s prodigious output makes short work of tough tasks.
We’ve been impressed by the GMC Sierra 2500HD’s interior ever since the refresh. Before, the design was bland and furnished with substandard materials. Now GMC dresses the cabin with an upscale design and premium appointments. Stepping up to the Denali Ultimate trim transforms the GMC Sierra 2500HD into a true luxury truck, although some controls are placed in inconvenient locations inside the cabin.
Equipping the AT4X or AT4X AEV trims ups off-road capability without sacrificing towing and hauling performance. However, if you really want to have fun on the trail, consider instead the smaller, cheaper Canyon AT4X AEV Edition.
GMC just needs to make a few more tweaks to propel the Sierra 2500HD to the top of its segment. Its grille is positively enormous and could turn off some buyers. The lack of GM’s excellent Super Cruise is a further drawback. Finally, higher pricing from the Chevrolet Silverado 2500HD would be better justified with a greater difference in entertainment tech and switchgear. Otherwise, we recommend shoppers consider the 2025 GMC Sierra 2500HD, especially if refinement and high-end trims are requirements.
Performance
GMC outfits most versions of the Sierra 2500HD with standard RWD and available 4WD. The upscale Denali and off-road AT4 trims receive 4WD as standard.
For motivation, the 2025 GMC Sierra 2500HD defaults to a 6.6-liter gasoline V-8 and a 10-speed Allison automatic transmission as its standard engine and transmission. Output is rated at 401 hp and 464 lb-ft of torque. In our testing of the 2024 GMC Sierra 1500 AT4X AEV Edition, we recorded a 0–60-mph time of 7.7 seconds.
A Duramax diesel engine is also available, yielding significantly higher horsepower and torque figures. The 6.6-liter turbocharged V-8 develops 470 hp and 975 lb-ft of torque. This powertrain also utilizes a 10-speed Allison automatic transmission. Models equipped with this diesel engine are quicker than gasoline models. We clocked a 6.5-second 0–60-mph sprint in the 2024 GMC Sierra 2500 HD Denali Ultimate and 7.1 seconds in a 2024 GMC Sierra 2500HD AT4X AEV.
Cab and Bed Options
Equipping the 2025 GMC Sierra 2500HD with its regular cab accommodates two or three passengers in a single row. Opting for available double or crew cab configurations ups the maximum capacity to six passengers.
The Sierra 2500HD’s long bed measures 98.3 inches long, while the shorter bed is 82.3 inches long. Both beds have the same width: 71.4 inches. The long bed can be had with the regular cab, double cab, and crew cab. Double and crew cab variants are available with the standard bed. GMC’s available MultiPro tailgate comes with clever features including a bed step, worktable, and cargo organizer.
Safety Features
GMC outfits the 2025 Sierra 2500HD with standard cruise control, front automatic emergency braking with pedestrian detection, automatic high-beams, and lane departure warning. New for 2025, a trailer brake controller is equipped on all models while front and rear parking sensors are found on more option packages. Rear cross-traffic alert with automatic braking, trailer blind-spot monitoring, and adaptive cruise control are available as part of packages or at higher trims.
Payload and Towing Capabilities
The 2025 GMC Sierra 2500HD’s maximum payload ranges from 3,381 pounds to 3,850 pounds depending on configuration. Towing tops out at 14,500 pounds on most models, but the rating climbs to 20,000 pounds on dually diesel models with the Max Trailering package. Technology
For 2025, GMC offers more tech across the Sierra 2500HD’s lineup. SLE models now come with a 120-volt power outlet in the cabin and a bed-mounted 120-volt power outlet and two USB ports.
The GMC Sierra 2500HD Pro works with a 7.0-inch touchscreen with connectivity features including Bluetooth, Apple CarPlay, and Android Auto. The basic Pro trim receives a 3.5-inch instrument cluster screen, while SLE trims and higher come equipped with a 12.3-inch driver display. These models also utilize a 13.4-inch touchscreen with wireless Android Auto and Apple CarPlay. Additionally, versions of the Sierra 2500HD equipped with the bigger screen also use Google built-in software, with Google Maps, Google Assistant, and the Google Play Store.
Higher-end models have USB ports in both rows of seats and a wireless charger up front. A six-speaker audio system is equipped on lower trims, while seven- and 12-speaker setups from Bose are available on higher-end models. GMC offers a camera system providing a 360-degree view of the Sierra 2500HD’s surroundings. There are views for parking, hitching to a trailer, and monitoring the bed.
Heavy-Duty Off-Roading: Sierra 2500 AT4, AT4X, and AT4X AEV Edition
Those who want off-road capability in addition to heavy-duty utility should option the AT4 or AT4X trims. The lower-level AT4 model comes equipped with off-road suspension, skidplates, 20-inch gloss black wheels, and a two-speed transfer case. Upgrading to the AT4X adds a 1.5-inch lift with Multimatic DSSV dampers, an e-locking rear differential, two frame-mounted vertical recovery hooks painted red, a 360-degree camera setup, and a stamped steel front approach skidplate. For more off-road hardware, the available AT4X AEV Edition package equips AEV’s stamped-steel front and rear bumpers with heavy-duty cast recovery points, 18-inch AEV wheels in Salta Black paint, and stamped steel body armor. This trim receives a number of cosmetic changes with AEV branding, with touches including floor liners, head restraints, and a tailgate badge. The door handles and tailgate are also accented in black. This model performs well off-road, but the large and heavy pickup is better suited for rock crawling than loose-surface fun. Denali Ultimate: Heavy-Duty Luxury
Going beyond the equipment offered on the standard 2025 GMC Sierra 2500HD Denali, the Denali Ultimate trim rides on model-specific 20-inch wheels. Further exterior accents include dark chrome finishing on the grille and badges. The interior is heavily upgraded over the rest of the Sierra 2500HD lineup: Leather, wood, and suede-like materials are used to imbue the pickup’s cabin with upscale ambiance. Heated and ventilated front seats offer 16-way adjustability and massage functionality. There’s also a sunroof, a huge head-up display, 12-speaker premium audio system, and wireless charging pad. Which 2025 GMC Sierra 2500HD Trim Level Is Best?
Pinning down the best version of the 2025 GMC Sierra 2500HD is a tough task; there are seven trim levels, two powertrains, and five styles of cab and box. The trim range includes the Pro, SLE, SLT, AT4, Denali, AT4X, and Denali Ultimate grades. We think the SLE is a solid pick, even though it’s one of the lower-level models. GMC still equips large displays with a robust suite of connectivity features inside the cabin. For 2025, there are upgrades available for the SLE trim, giving you the ability to start at a lower MSRP before adding on safety or convenience packages. The SLE undercuts the SLT by a whopping $7,000, money that can instead be spent on the tremendously powerful Duramax diesel engine and 4WD.
