2020 GMC Sierra 1500 DieselDerek McNaughton / Driving JACKSON HOLE, Wyo. General Motors, after announcing last January it was bringing a diesel engine to its Sierra and Silverado light-duty pickups, delayed releasing power and torque figures for what seemed like forever. The reason? Its brand new 3.0-litre baby Duramax engine, developed specifically for the freshly redesigned pickups, had to compete with Ford’s new diesel in the F-150, as well as a looming update to the long-running EcoDiesel in the Ram.Ford had come out swinging with 440 lb.-ft., besting the Rams 420. Most figured GMs new 3.0L diesel would, at the very least, produce 450. But in March of this year, GM Authority revealed the secret: The 3.0L Duramax would come with an SAE-certified 277 horsepower and 460 lb.-ft. of torque, making the Sierra and Silverado the most powerful half ton diesels on the market. And for a few short months, GM proudly wore the crown.But competition and bragging rights in this category matter and RAM, never to be outdone raised the stakes by recently proclaiming its EcoDiesel would deliver 480 lb.-ft., although less overall horsepower than GMs pair of trucks. The torque war was suddenly on full display and GM lost its best-in-class status. But while GM may have lost the early numbers battle, it may have won the war simply through intelligent engine architecture: Instead of using a V6 for its diesel, GM chose a straight six a configuration long known for its inherently superior balance and buttery smooth delivery of power.That decision paid off. Touch the throttle on the 2020 Sierra equipped with the diesel and the reaction is quick, only the slightest pause as the Hydra-Matic 10-speed automatic transmission figures out where it needs to be before unleashing the engines full fury. Astonishing in force, the small diesel rockets the Sierra ahead with power that feels as strong and stout as GMs 6.2-litre V8. And, wow, is it ever smooth, with just enough feel through the cabin and steering wheel. Exceedingly quiet at idle, the engine delivers an almost BMW-like roar under full power, a hearty mix of turbocharger, high compression, and pistons all surging in perfect harmony. Engineers say they worked specifically on the intake sound, combining an air induction system with noise-reducing elements. Instead of blanketing the engine sound, GM has enhanced it. Yes, theres a bit of diesel clatter at throttle tip-in as would be expected and nearly impossible to eliminate, but in simple cruising theres just a low and deep and pleasing hum to the engine. Even though Ram has more torque, theres something about this engine that simply feels better behind the wheel, more satisfying when the foot hits the floor.No doubt some of that comes from an engine mount solenoid that basically acts as an adaptive shock absorber to control vibration and lower NVH levels. But some also comes from an aluminum cylinder head that caps an aluminum block (with iron cylinder liners for durability) to reduce mass over the front wheels. A variable-geometry turbocharger adjusts boost pressure according to demand, and air flow into the intake manifold is electronically controlled.An inline-six also has less moving parts than a traditional V6 two fewer camshafts and the chains to drive them, so theres no need for balancing shafts. Overall friction is less, too, all of which resulting in a clean, higher purity of power that begins to peak in this engine as early as 1,250 rpm and summiting at 1,500 rpm, sustaining itself through 3,000 rpm.Stepping on the gas returns some long legs of power, tapering off only after the truck blows past 110 km/h. Like a performance car, the Sierras power is constantly tempting and teasing the driver to explore its depths. Its almost too much seduction for a truck. If I were ordering a Sierra tomorrow, there is no doubt what engine Id choose, even if it does cost an extra $3,135 and is available on all trims (except the base truck) and only in double and crew cabs. Thats also because Im frugal, and would love to be able to travel more than 1,000 kilometres between fill-ups as the Sierra diesel should. Transport Canadas official rating for the 4WD diesel is 10.5 L/100 kilometres city, 9.1 highway and 9.9 combined. Two-wheel-drive trucks get an 83-litre fuel tank, while 4WD trucks get a 90.Mileage in the real world might skew lower, too, more toward the estimates on the Chevy Silverado which can be optioned with the same engine and returns 8.0 highway and 10.4 city on 4WD trucks. GM says the Sierra has more content and typically wears more aggressive tires that affect fuel economy. Based on the couple of hours we spent driving the Sierra on some mountainous roads, we achieved a low of 7.6 L/100 kilometres in some steady, 90 km/h driving, while the longer average on the trucks computer showed 11.2, though we had no idea how hard the truck was driven before our drive or how much it was idled.
Origin: First Drive: 2020 GMC Sierra 1500 Diesel

2020 GMC Sierra HD DieselDerek McNaughton / Driving JACKSON HOLE, Wyo. Pulling a 13,000-pound Keystone Cougar trailer up and down mountain roads for a summer vacation is not going to be stress free nor is it something that can be typically done in a half-ton pickup, even if the maximum tow rating of said half-ton is 13,200 pounds. For massive loads like these, a heavy-duty truck is the only way to go.Ford, Ram and GMC all produce HD trucks, of course, but GMC has the newest HD on the market. The 2020 GMC Sierra 2500 HD diesel is not just a towing machine, its a leather-lined luxury cruiser that coddles its occupants in quiet and technology as much as it works to carry big things.Taller and longer than its predecessor, the 2020 Sierra HD looks especially good without being overwrought or too blingy the way other trucks sometimes tend to get, especially in the new AT4 trim, which looks perfect without all that chrome. Proportions on all the HD trucks are just about ideal, the bed made lower by one inch and three inches of legroom added to the crew cab, while the larger grille complements a functional hood scoop that feeds the cooling system for the Duramax diesel. New side steps on all box styles, located just behind the rear door, smartly pair with truly functional (and now deeper) rear-bumper steps. GMCs unique, six-way MultiPro tailgate is also available on all trim levels and standard on some, although its use is limited when a hitch is in the receiver.But the diesel is the real draw in the Sierra 2500. A 6.6-litre turbocharged V8 with cast iron block and aluminum heads, the diesel will deliver 910 lb.-ft. of torque as early as 1,600 rpm and 445 horsepower peaking at 2,800 rpm, meaning full power arrives early without having to wring out the engine for all its got. The diesel is actually more detectable by the badging on the front fender than it is at idle. Even under load, this engine is no noisier than a gasoline engine on the highway, although it is far more efficient. We were able to achieve an astonishing low of 8 L/100 kilometres in some very gentle 90 km/h driving with a 2,000-pound payload in the bed and no trailer, but averaged closer to 11 without trying to be thrifty. While towing the big Keystone through Wyoming, we dropped to an average of 25 L/100 kilometres. Good thing crew-cabs get a 136-litre tank, which would mean a little over 500 kilometres of travel when pulling a massive trailer through the mountains, or roughly 1,200 highway kilometres in regular use.The standard engine on the 2500 HD truck is a 6.6-litre gasoline V8 with 401 horsepower and 464 lb.-ft. of torque. Diesel adds an extra $11,195 to the base price of $46,998 for the regular cab, two-wheel-drive short box.And the diesel brings the power. Sure, going up some long uphill grades with that big trailer, the Sierra HD wouldnt much budge beyond 100 km/h even with a foot to the floor, but it had no difficulty maintaining a constant 90 uphill. Better was coming downhill and using diesel-exhaust braking, which can hold the trucks speed during a descent in combination with what should be a bulletproof 10-speed Allison automatic transmission the first-ever 10-speed in the HD segment, but expect to see a 10-speed in the competition soon.It certainly makes towing gentler, the transmission ironing out the shift points so perfectly they are almost not noticeable. I only wish there was a solution to the old-school column shifter, in an interior that doesnt exactly overwhelm with its sophistication. The primary center screen could easily be much larger, but at least theres a good compliment of knobs and buttons, and a proper restraint in using too many digital controls. Compared to the previous-generation truck, the 2020 Sierra HDs new architecture feels quieter overall and more tightly welded together. Brakes are smooth, the steering tight, the ride surprisingly comfortable given how tightly sprung the suspension is for the weight its meant to tow. Maximum conventional towing on the 2500 diesel is rated at 18,500 pounds in crew cab form, with a max payload of 3,597 pounds. With a gooseneck or fifth-wheel set up, the number is the same.As before, the HD trucks can be ordered in myriad bed and cab configurations in the 2500 and 3500 range, available with either a six-foot-nine or an eight-foot bed. Also available is a 15-inch head-up display, another first among HD trucks. The 2500 can also be optioned with GMs ProGrade trailering system that also includes an in-vehicle trailering app to check lights, trailer tire pressures, and even how much fresh water or wastewater is in the holding tanks of the trailer.An optional camera system can show up to 15 unique camera views including an industry-first transparent trailer view. Using the tailgate camera and a camera mounted on the rear of the trailer, software mixes the views of both cameras to make the trailer in back look invisible. That should help remove a
Origin: First Drive: 2020 GMC Sierra HD Diesel