Specifications of GMC Sierra 2500HD Double Cab Standard Box 2500 6.6 TD V8 (445 HP) 4WD SRW Automatic
General characteristics of GMC Sierra 2500HD Double Cab Standard Box 2500 6.6 TD V8 (445 HP) 4WD SRW Automatic
The Sierra 2500HD is a big vehicle in any configuration. The smallest of the bunch is the Regular Cab with the long bed, which measures at 235.5 inches in length. The longest is the Crew Cab with a long bed, which measures 266.09 inches in length. The overall width of this truck ranges between 81.75 and 81.85 inches, while the overall height varies between 79.65 and 79.95 inches, depending on the model.
The front track on all models is 68.1 inches while the rear track is 68.3 inches. Max ground clearance is just over ten inches. The lightest truck on offer is the gas-powered Regular Cab with a curb weight of 6,105 pounds. On the other side of the spectrum, the Crew Cab with the diesel engine, 4WD, and the long bed weighs as much as 7,886 lbs.
A big and bold truck deserves a big and bold color palette, and GMC does not disappoint in this regard. The base model can be finished in your choice of six colors, with Summit White being the only no-cost option. The other five colors on offer cost $495 each and include Cardinal Red, Onyx Black, Pacific Blue Metallic, Quicksilver Metallic, and Brownstone Metallic. The SLE adds Ebony Twilight Metallic and Cayenne Red Tintcoat, the latter being a pricier $645. The SLT can be painted with a White Frost Tricoat for an additional $1,095, though the AT4 doesn't get the same option. The Denali gets exclusive access to Hunter Metallic and Carbon Black Metallic, both of which carry the same $495 charge. However, this model loses the Brownstone shade. The AT4 has its own limitations as well as. For instance, it isn't compatible with Carbon Black or Cardinal Red.
Those looking to buy full-size trucks will mostly care about factors such as towing capacities, load capacities, and torque figures, and the GMC Sierra 2500HD offers plenty of each. Under the hood, you get the option of a 6.6-liter gas V8 or a 6.6-liter turbodiesel V8. The former produces 401 hp and 464 lb-ft of torque, while the latter churns out 445 hp and 910 lb-ft. The Sierra 2500HD can be configured in RWD or 4x4 guise. No matter what engine you go for, the GMC Sierra offers excellent performance, but those looking for a serious working truck will prefer the massive torque output of the 6.6-liter turbodiesel engine. The performance figures are impressive: independent testing has shown that the diesel will manage a best 0-60 mph sprint in under seven seconds and under 20 seconds when pulling a trailer weighing 18,000 pounds. The maximum towing capacity is 18,500 lbs for diesel-engine Crew Cab trucks, but gooseneck trailering ups that to 18,510 lbs for the diesel 2WD model in Regular Cab form. The maximum payload capacity is 3,979 lbs, which applies to the 2WD Regular Cab with the gas engine.
GMC doesn't beat around the bush when it comes to power, and you won't find any 4-cylinder engines here. Under the hood of the 2021 GMC Sierra 2500HD, it's strictly V8 power. The 6.6-liter V8 gas engine was first introduced in 2020 and produces a healthy 401 hp and 464 lb-ft of torque. Power is sent to the rear or all four wheels via a heavy-duty, electronically controlled six-speed automatic transmission. This engine does a convincing job of hauling this large truck around town, and you'll never be left wanting for power, but you'll be left with the nagging reminder that there is a more powerful option on the table. The 6.6-liter turbodiesel V8 engine is the one to go for if you want all the power and bragging rights. With 445 hp and a mammoth 910 lb-ft of torque on offer, this engine makes short work of heavy trailers, and thanks to a silky 10-speed auto transmission, the diesel boasts smooth, hassle-free power delivery. Either way, both power plants are up to the task.
Full-size trucks have come a long way in terms of drive comfort and handling ability, and the GMC Sierra 2500HD is up there with the best of them thanks to its use of an independent front suspension. Not only does this little party trick make the ride more comfortable than ever before, but it also helps the truck feel more eager to turn in and more maneuverable in general. This is great for city driving but also helps a ton when taking on the great outdoors. When it comes to towing, it is amazing how comfortable the 2500HD is; this truck will make an excellent long distance cruiser. It helps that both V8 options barely feel strained when hauling a trailer on the open road.
Off-road, the 2500HD is a capable machine but can be a bit big for tight trails. The AT4 trim adds all-terrain tires and a two-speed transfer case, as well as an off-road-tuned suspension for increased capability, and it pays off. The exhaust brake function is highly effective at keeping the brakes from overcooking.
Last year's redesign did wonders for the Sierra 2500HD's appeal: it's an attractive truck to look at, but unfortunately, the same cannot be said for the inside of the cabin. The design seems rudimentary and out of date when compared to rivals from Ford and Ram, and the choice of materials isn't that impressive either. Denali models do an excellent job of lifting the cabin with plusher materials, but the design remains an issue. Thankfully, there's a lot of interior space to thrash about in disappointment. In base form, this is a simple working truck that offers vinyl seats and manual windows, but the higher up you go, premium features such as rear-seat infotainment and navigation become available.
Five models make up the range, but as we found in prior reviews, don't expect anything spectacular at the lower end. The base-model Sierra comes with only the basics such as manually adjustable vinyl/cloth seats, a 3.5-inch diagonal monochromatic driver information display, single-zone climate control, a rearview camera, and dual USB ports. The SLE adds features such as cruise control, cloth seats, a leather steering wheel, a compass, and a 4.2-inch digital cluster. The mid-range SLT's specs are more impressive and include a 10-way power driver seat with power lumbar support, leather upholstery, heated front seats, dual-zone automatic climate control, hitch guidance with hitch view, and remote start. The off-road AT4 adds features such as front bucket seats with ventilation, heated rear outboard seats, and a front center console. The range-topping Denali includes an eight-inch digital driver info center, a bed-view camera, HD surround vision, a universal home remote, and wireless charging. A 15-inch diagonal multi-color head-up display is available optionally.
The infotainment system has become a critical selling point for most modern vehicles, even heavy-duty trucks, so it is disappointing to find a small seven-inch touchscreen display in the base model Sierra 2500HD. At least the system is quick to respond to inputs. The base system comes with Bluetooth streaming, an AM/FM radio, a six-speaker sound system, and Android Auto and Apple CarPlay integration. However, the base Regular Cab makes do with only two speakers. The SLE adds 4G LTE Wi-Fi compatibility and SiriusXM radio. The SLT gets a larger eight-inch display with wireless phone projection, SiriusXM 360 L, and voice-activated technology. The top-of-the-range Denali adds navigation and a seven-speaker premium Bose sound system that does a much better job of playing back your favorite tunes.
The 2021 GMC Sierra 2500HD has so far been subject to two recalls based on the NHTSA's records and both had to do with the seat belts. In both cases, occupants may not be properly restrained in an accident. This could be due to either a seat belt bracket that isn't secured or, in the case of the more recent recall, incorrect bolts used to attach the belts. One of these issues carried over from 2020, which saw five recalls issued for the truck. These recalls included unsecured front seatbelts, defective roof-rail airbags, two recalls for an unsecured hood that may open unexpectedly, and seatbelt pre-tensioner issues.
GMC covers the Sierra 2500HD with a three-year/36,000-mile warranty, a five-year/100,000-mile powertrain/drivetrain warranty on diesel engines or for the same time period but just 60,000 miles in the case of the gas engine. A one-year/one visit maintenance plan and a five-year/60,000-mile roadside assistance plan are also included. For the latter plan, the coverage extends to 100,000 miles in the case of the diesel model.