GMC Sierra 2019

Body, cabin and cargo space

The GMC Sierra still comes with a choice of three cabs—regular, double and crew—and three bed lengths (5 ft. 10 in., 6 ft. 7 in. and 8 ft. 2 in.). Our AT4 tester paired the longest cab (crew) with the shortest cargo box, a popular combination that favours handling and interior space over cargo volume.

Meanwhile, AT4 and Denali add to the versatility thanks to their MultiPro double hinged tailgate. The primary gate lowers independently, then an inner secondary gate and a smaller panel unfold for a total of six different functions. This includes a fold-down step feature that we found very practical to access the bed.

Be careful, however, not to leave anything in the trailer hitch if you lower both sections of the tailgate, to avoid damage to the upper panel. Thankfully, we always remove the ball mount once our trailer is set up; otherwise, our weekend camping trip with a GMC Sierra would suddenly have become much more expensive.

Practicality is also a dominate feature inside the crew cab. There is plenty of space for five, even for a middle passenger in the back. The wide front bucket seats provide good support, and all our testers appreciated their comfort.

The bucket seats are optional in the less expensive models; the standard split bench seat is not as well shaped. GM has fixed the problem of the offset driving position of the former model and added a well-placed dead pedal. Once again, the most affordable Sierras are deprived of a telescoping steering wheel, a penny-pinching move that is completely out of step with the times.

In contrast, all models now come with at least a 17.8 cm/7 in. centre touch screen with an updated interface that is much more user friendly. Buttons facilitate access to the main functions, but to get a tuning dial, you have to opt for the optional 20.3 cm/8 in. display. In terms of connectivity, a standard 120V outlet can round out the USB ports, LTE wireless modem, Bluetooth and Android Auto/Apple CarPlay, all standard.

Other highlights

Rear seating: flat and firm, the bench is very wide, with room for three child car seats depending on the type. Split seat cushion flips up to create a vast cargo space; seatbacks do not fold down. Rather narrow open compartments under the seat; hidden compartments in outboard seatbacks. Heated seats, air vents, folding armrest and charging ports available or not, depending on trims.

Instruments: simple, easy-to-read dials and trip computer. Very practical optional head-up system, comprehensive and exclusive in the pickup segment.

Finish: good-quality perforated leather and some soft-touch plastic surfaces on top-end versions; hard, cheap plastics on all models. Hit and miss interior fit. For the $78,000 price of our test model, Ford F‑150 and RAM 1500 offer a much more luxurious cabin.

Storage: dual glove compartment, a bin large enough for a knapsack under the centre armrest and open bin in the console (with the bucket seats), front/rear cup holders with retention tabs, and large door pockets. Available charging pad.

Safety features

• Antilock brakes with brake-force distribution and brake assist
• Stability and traction control
• Hill-descent control (standard on Denali and AT4, included in X31 all-terrain package on other versions)
• Front airbags
• Front side airbags
• Side curtain airbags
• Front safety belts with pretensioners
• Five or six adjustable head restraints
• Rear passenger reminder
• Rearview camera
• Tire pressure monitor
• Trailer tire pressure monitor (optional, SLT, AT4 and Denali; unavailable on other versions)
• Surround view monitor (included in AT4 and Denali Technology package; unavailable on other versions)
• Parking sensors, blind-spot warning and rear cross traffic alert (standard, Denali; included in Driver Alert I on other versions)
• Frontal collision alert with automatic low-speed emergency braking and pedestrian detection, lane departure warning, lane keep assist and automatic high beams (included in SLT, AT4 and Denali Driver Alert II; unavailable on other versions)

Crash test results

National Highway Traffic Safety Administration (NHTSA)
Overall score: 4 / 5
Frontal impact: 4 / 5
Side impact: 5 / 5
Rollover resistance: 4 / 5

Insurance Institute For Highway Safety (IIHS)
Moderate overlap frontal impact: 4 / 4
Small overlap frontal impact:
- driver side: 4 / 4
- passenger side: 2 / 4
Side impact: 4 / 4
Rear impact: 4 / 4
Roof strength: 4 / 4

Visibility

Extremities of vehicle easy to situate thanks to the large glass surface, very horizontal hood and vertical sides. Large centre roof pillars hinder lane changes; big mirrors and blind-spot monitoring compensate adequately. Multi-angle camera and surround monitoring system a huge help when hitching up a trailer and parking it in tight quarters.

Headlights: even though the LED headlights generally light up a good distance, the Insurance Institute for Highway Safety (IIHS) gives them a poor rating because of the glare they create.

Mechanical overview

GM thoroughly revised the frame of its pickups to improve safety, sharpen the balance of comfort and handling and increase the towing and hauling capacity.

The new chassis contributes to a weight reduction of about 100 kg along with the use of aluminum for the hood, doors and tailgate. An additional 62 kg can be shed by opting for a new carbon fibre cargo box starting in 2020.

Under the hood, the GMC Sierra offers no less than six engine choices. Most buyers will no doubt opt for one of the three available V8s, including our tester’s impressive 6.2 litre. Still equipped with a central camshaft—a solution as old as the automobile—this engine nevertheless is packed with modern technologies aimed at refining the power/fuel economy ratio. Examples are variable valve timing, deactivation of one to six cylinders depending on demand and an automatic start/stop system.

All of that hardware is also found on the 5.3-litre V8 that will account for the majority of sales. The base model can be ordered with the preceding generation of this engine in addition to the standard 4.3‑litre V6.

GM takes a bold step by offering a 2.7‑litre turbocharged four-cylinder on SLE and Elevation models, the top sellers of the lineup. With 310 horsepower and 348 pound-feet of torque, this engine slots between the V6 and the 5.3‑litre V8 in terms of power. Even though it costs $1,695 less than the V8, the very idea of a four-cylinder in a full-size pickup may risk destabilizing target buyers… time will tell.

The automatic transmission is a six-speed on the base-model Sierra and eight-speed on all the other models, unless they are equipped with the 6.2‑litre engine. The latter is exclusively mated to a Ford-designed ten-speed gearbox. Under an agreement with Ford, GM manufactures its own version of the transmission that it programs specifically for its models.

All 4X4 versions of the GMC Sierra—and not just the high-end models like much of the competition—include an automatic power split mode. Normally, you only engage four-wheel drive on a pickup on a surface that is already slippery, to avoid damaging the system. Automatic mode greatly reduces the risk of being taken by surprise by a sudden loss of traction.

In terms of fuel economy, Natural Resources Canada lists a city/highway combined average of 11.8 L/100 km for a four-cylinder 4X4 model. The rating peaks at 14.3 L/100 km for the 6.2‑litre engine Sierra AT4 we tested. Ratings for the diesel engine had not yet been announced when this article was published.

We obtained a result of 13.4 L/100 km on a run that included two-thirds highway, then 17.7 L/100 km while towing a 1,000 kg/2,200 lb camping trailer on mainly flat roads.

Towing capacity varies from between 2,948 kg/6,500 lb to 5,534 kg/12,200 lb, depending on the cab, engine and two or four-wheel drive.

Driving impressions

The first thing that impresses behind the wheel of the GMC Sierra AT4 is the performance of the optional 6.2‑litre engine. Flexible and powerful at all levels, it emits a richly sonorous note that is sure to thrill pickup truck fans. Accelerating in this pickup is a true guilty pleasure, especially with the optional performance exhaust system.

However, the system pushes the engine note to an unpleasant level at highway speeds. It also exposes the functioning of the cylinder deactivation system with changes in tonality and the occasional vibration.

The ten-speed automatic transmission provides masterful support to the big V8 thanks to its ideal gear spacings. It functions with a level of smoothness that is rare for a transmission with that many gears. However, you sometimes have to insist a bit to get it to downshift, though those occasions are rare because of the abundant engine torque. Towing mode is so efficient that you seldom feel the need to shift manually.

The AT4 version we tested proved secure and stable on the highway despite its high ground clearance and the rather soft-sided all-terrain tires. The tires produce an audible whine, similar to snow tires, and they accentuate the vague, relatively imprecise steering that sometimes requires correction while negotiating a curve.

Road holding is acceptable on winding roads as long as they are smooth. Hitting a crack in a turn can cause the rear end to bounce sideways, even at moderate speeds. The suspension is jouncy and allows several impacts to reach the cabin. The off-road tunings and shocks admittedly amplify the firmness of the AT4’s ride, but it is far short of the smoothness of a RAM 1500 or the balance of a Ford F‑150 on the road.

Unless you often head off the beaten path, or the macho look of the Sierra AT4 is an absolute must, you are probably better off with another trim level, without the all-terrain package. For example, the Denali’s adaptive ride control suspension is much more civilized on the road.