CALGARY, Alta. - It is not a stretch to say that Western Canada is a vital market for automakers selling trucks, particularly the full-size variety - and if you've ever seen a Calgary parking lot, you already knew that.

This is especially true for the Detroit Three - Ford, GM and Stellantis - whose full-size pick-ups accounted for four of the ten bestselling new vehicles in Canada in 2025. Take GMC: the Sierra pick-up was not only the bestselling GMC vehicle in Canada in 2025, but also the top-selling GM vehicle overall, beating the Chevy Silverado. Its top sales market was Western Canada, which GM defines as Manitoba west to British Columbia. This territory is also GMC's best sales region for its SUVs. In short, Western Canada matters a lot to GMC.

The value of this market is exemplified by GMC's relationship with the Calgary Stampede, the annual rodeo and festival that began in 1912 and attracts over one million attendees each year. GMC has been a Stampede partner since 1986, and its presence is everywhere at Stampede Park, including GMC Stadium, a 17,000-seat grandstand.

AutoGuide was invited to Calgary to sample several GMC products, so we strapped on our best cowboy hat and boots and hit the Rocky Mountain roads. First up: the Sierra 2500 HD AT4X AEV. This truck is monstrous. Climbing in and out felt like a mountaineering exercise. At more than 20 feet (six meters) long, almost seven feet (two meters) wide, and six-plus feet tall, it's one of the biggest trucks we've recently driven. Powered by a 6.6-liter Duramax diesel V8 producing 470 horsepower and 975 lb-ft of torque, it's ready for anything. Payload: 3,411 pounds (1,547 kg); towing capacity: 20,000 pounds (9,072 kg) with a trailering package. We didn't tow or haul, but rest assured, it can do both. We didn't off-road either, but the AEV edition - courtesy of American Expedition Vehicles - is capable of serious overlanding, thanks to stamped steel bumpers, skid plates, and 18-inch AEV Salta wheels on a 1.5-inch factory suspension lift with Multimatic DSSV dampers, a rear electronic-locking differential, and 35-inch all-terrain tires. On-road, it delivers a comfortable ride on smoother tarmac, but the heavy off-road spec can get bouncy on rougher pavement. Our Volcanic Red Tintcoat Sierra 2500 handled it well, with a luxurious interior and surprisingly low diesel noise.

Next, we sampled a Sierra 1500 Denali Ultimate towing a 26-foot (7.9-meter) trailer weighing 10,000 pounds (4,535 kg) through a mountainous pass from Calgary foothills to Kananaskis village (elevation 5,217 feet / 1,590 meters). Power came from GM's 6.2-liter V8 (420 hp, 460 lb-ft) paired with a 10-speed automatic. Towing capacity: 13,200 pounds (5,987 kg). It handled the load well, with some jerkiness under acceleration but smooth and steady at 55-62 mph (100-110 km/h). The tester also featured Super Cruise, GM's hands-free driving aid, which worked well for hands-free trailering - a feature GM alone offers. The interior was loaded with wood and leather, a 13.4-inch infotainment touchscreen, and a 12-speaker Bose audio system.

Finally, we drove the Terrain AT4, GMC's entry-level SUV. Our Volcanic Red Tintcoat tester sits in the middle of the lineup (Elevation at bottom, Denali at top). All Terrains use a 1.5-liter turbocharged four-cylinder (175 hp, 203 lb-ft; FWD Elevation gets 175 lb-ft). Transmissions: CVT for FWD Elevation, eight-speed automatic for AWD grades. The third-gen 2025 model brought digital displays: an 11-inch instrument cluster and a 15-inch portrait infotainment touchscreen, both pin-sharp. AT4 features include driver-selectable terrain mode, lifted ride height, front recovery hooks, a front skid plate, and 17-inch dark machined wheels with all-terrain tires. On-road, it accelerates well and feels secure. The cabin impressed with heated front seats and a heated steering wheel, feeling premium despite costing less than half the pick-ups.

The Calgary Stampede is a feast for the senses - even for non-cowboy types. We enjoyed chuckwagon and relay racing (the latter is simply wild), and a grandstand show with bands, acrobats, and more fireworks than the 4th of July. GMC's name is plastered everywhere, and a big auto-show display sits in the midway. After 40 years of partnership, it appears GMC plans to stick around for another 40.