2024 GMC Sierra 2500HD Reviews, Pricing & Specs

Fans of large grilles will give the Sierra HD Denali Ultimate a 10 out of 10 based on looks alone. There’s no doubt the scale of the HD gives it a road presence that’s only rivaled by 18-wheel tractor trailers—which, incidentally, you’re nearly level with when behind the wheel of this GMC truck.

Our tester was finished in Onyx Black paint, Alpine Umber tan interior, and rode on 20-inch aluminum alloys with gloss black inserts. Six other exterior colours are offered, though our HD’s Darth Vader-like visage gave it a menacing attitude that parted traffic wherever we roamed. There are six other 20-inc wheel choices and two 22-inch options for the Denali Ultimate in Canada, including a set of 20-inch chrome alloys which, at the time of writing, cost a hefty $4,965. Then again, for a pickup with a starting price of approximately $125,000 (including destination fee), that’s a drop in the proverbial pickup truck budget.

For the 2024 model year, the entire HD lineup receives an updated front bumper and grille assembly with standard LED headlights and taillights. It also has newly added sequential turn signals. With the Denali Ultimate trim the only choice of cabin is the six-passenger Crew Cab, though you can pick between two cargo bed lengths. This includes the standard bed at 2,088 millimetres (82.2 inches), or the long bed that runs to 2,494 mm (98.2 inches). Handy side steps are worked into the sides and rear bumper corners of either bed for easy access to whatever load you’re hauling.

The Denali Ultimate also comes standard with GMC’s versatile MultiPro Tailgate which can flip and fold into six different configurations, including a workbench, a step for the cargo bed, or as a means of extending the bed’s length for bulkier cargo. Those working late shifts might be tempted to add optional MultiPro step lights ($280) to ensure safe cargo-bed-climbing at nighttime.

Unlike the standard Sierra HD trims that offer a 6.6-litre V8 gas engine as standard, the sole engine found under the helipad-size hood of the HD Denali Ultimate is a 6.6-litre Duramax turbocharged diesel V8. It produces power specs of 470 horsepower and, wait for it, a staggering 975 lb-ft of torque.

The Duramax turbodiesel is coupled with a stout 10-speed Allison automatic transmission and standard four-wheel drive (4WD). Additional mechanical hardware includes a locking rear differential, two-speed transfer case, all-terrain tires, heavy-duty air filter, underbody skid plates, hill descent control, and a diesel exhaust brake to boost stopping power when trailering heavy loads.

From a standstill, punching the gas pedal got our tester down the road smoothly and quickly, considering it tips the scales at more than three tons. Highway passing power is strong, and the powertrain displays a high degree of refinement. It even sounds good; there is little to none of the ‘tap tap tap’ diesel clatter you expect from, well, a very large diesel engine fitted to one very large pickup. The automatic transmission never hunted to find the right gear, and this aided the HD’s performance in every type of driving situation.

Handling is dictated more by the HD Denali Ultimate’s size than feedback between the front wheels and your fingertips. So long as you have plenty of space, it feels reasonably agile when navigating city or highway traffic. But be prepared to pick a spot toward the back of every parking lot, unless you want to embarrassingly go forward…reverse…forward…reverse…forward again etc. Consider the HD’s parking lot bulkiness an excuse to get some added steps in each day.

To be fair, the firm ride and toughened-up suspension settings of the HD Denali Ultimate are dictated by this truck’s main dual purposes of towing and hauling. On smooth roads it’s fine and the lofty seating position gives an expansive view. Yet during a week-long test that covered more than 1,600 kilometres, we discovered potholes and rough pavement easily unsettle the unladen suspension. Bridge expansion joints in particular could lead to a see-saw, front-to-back rocking motion that was only alleviated by significantly slowing down to let the truck regain its composure.

As the top-of-the-line trim, the HD Denali Ultimate is fitted with full-grain leather across the front and rear seats, leather-covered door panels with stainless-steel speaker grills, a microsuede headliner, wood trim, leather-wrapped steering wheel, and even leather-wrapped A- and B-pillar handles to hoist yourself onboard. Not that you’ll need to use them much, considering power-operated running boards are standard (and certain to be hugely appreciated by anyone shorter than an NBA power forward).

Stretch-out room and in-cabin storage is superb, to put it mildly. The front seats are wide, supportive, and left us feeling refreshed even after a nine-hour-plus drive. In the Denali Ultimate these perches are heated and ventilated, and also come with a massage function. As nice as they are, the rear seat is equally impressive for its limo-like legroom and cowboy-hat-friendly degree of headroom. Three adults will have no problem residing back there for long road trips.

Storage space is excellent. The centre console alone has room for drinks, mobile phones, or whatever else you care to tuck inside. It can even be optioned with a locking safe in the main storage compartment.

Just be careful about putting anything essential in the front door pockets. While driving and trying to reach way, way down to access smaller items stored there…let’s say that was a task we attempted only once. All beverages and road snacks were soon relegated to easier-to-reach nooks and crannies.

While lesser Sierra HD models make do with a standard 8.0-inch touchscreen, the Denali Ultimate features a 13.4-inch screen and a hoard of tech features befitting a work-meets-luxury truck. This includes a 15-inch multi-colour head-up display, wireless Apple CarPlay and Android Auto connectivity, wireless device charging pad, Google built-in, 12-speaker Bose surround-sound audio system, and split-screen navigation.

The navigation system is so sharp and accurate, it could convince a few truck owners to forego automatically opting for smartphone-based navigation apps when hitting the open road. Wisely, GMC kept the climate control system in a row of convenient buttons and dials below the touchscreen. This avoids the annoyance of taking your eyes off the road to accomplish something as simple as adjusting temps or fan speed.

One very non-tech cabin item that negatively impacts GMC’s otherwise impressive interface is the steering-column-mounted stalk to shift gears. Slotted into Drive and viewed from the driver’s perspective, this bulky beam of plastic blocks a large portion of the centre screen. Case in point, when a certain navigation-based app was being used, the gearshift stalk was (im)perfectly positioned directly in front of info related to drive time and distance remaining.

Back in the positive column, the HD Denali Ultimate comes with a wide range of trailer aids such as a trailer-brake controller, hitch guidance with hitch view, 2.5-inch receiver hitch with 4- and 7-pin connectors, and vehicle trailering app. It also comes with the ProGrade trailering system that serves up 14 different camera views. This includes angles for blind spots alongside a trailer, a cargo bed view, and what’s called Transparent Trailer View. This allows the driver to virtually see through whatever is being towed during fifth wheel/gooseneck towing.

Pickup trucks are no longer the exception to the rule that a vehicle should come with a reasonable amount of active safety features and driver assistance technologies. Features like automatic emergency braking and forward collision warning are now expected in everything from basic economy cars to high-riding workhorses like the HD Denali Ultimate.

The GMC Sierra HD comes standard with both of these features, along with others such as pedestrian detection and lane departure warning. Front and rear parking sensors, a surround-view parking camera, adaptive cruise control, rear cross-traffic alert, blind-spot monitoring, and a rear-facing cargo bed camera are optional features, and all are standard on the Denali Ultimate.

The extra large and power-operated side mirrors also deserve mention for giving an expansive view along either side of the truck. They can be extended further away by several centimetres for an even wider side/rearward angle—but make sure they’re tucked back inward on narrow one-lane highways, or during visits to the car wash.

In Canada, there are seven trims for the GMC Sierra 2500HD: Pro, SLE, SLT, the off-road oriented AT4, Denali, the upgraded off-road trim AT4X, and Denali Ultimate, which represents the top of the line-up. Pro and SLE are the only trims available with a regular cab or a double cab; the rest are sold exclusively in crew cab configuration with a short or long bed. From AT4 up, 4WD is standard. The 2024 GMC Sierra 2500 Denali Ultimate heavy-duty pickup truck has a base price of $125,630, including the $2,200 destination charge and other fees. We’ll let you take a moment to let that figure sink in.

True, that’s a serious amount of cash for any vehicle, never mind a work truck. But it’s on par with upper trims offered in the Ford Super Duty and Ram HD lineups. The question is more whether you need nearly every available feature loaded onto your GMC pickup, or if less expensive trims with carefully selected options are the better route.

Also, let’s not forget the proverbial General Motors elephant in the room, being that the GMC Sierra HD is mechanically identical to its less pricey sibling, the Chevrolet Silverado HD. The Chevy doesn’t have the same degree of plush cabin trim or other luxury touches, though it’s significantly less expensive. The highest trim of the Silverado 2500 HD is presently the High Country. Fitted with standard four-wheel drive and the optional Duramax diesel, it starts at roughly $101,724.

Because Natural Resources Canada doesn’t test heavy-duty trucks like the HD Denali Ultimate, we can only report on what we observed. During long highway stints the Duramax diesel dipped as low as 11.2 litres per 100 kilometres. At suburban/city speeds, however, we routinely saw economy ratings crest well beyond 20 L/100 km. A 136-litre fuel tank provides long-legged driving distances between each refueling. But when it’s time to fill up, try not to look at the end result once the fuel pump numbers stop spinning.

Note: Images show a US model.