In the period of the late 1940s and early 1950s, when pickups really started to win over workers and entrepreneurs, they were uniformly equipped with 6-cylinder engines.
Gradually, V8 engines started to find their way into pickups, and they eventually became the weapon of choice for work-focused trucks, which had to have strong towing and load capacities. For a long time, V6 and V8 mills continued to coexist, the former usually found in more affordable models that displayed diminished but still acceptable capacities.
So it remained until relatively recently. In the last few years, however, two new realities have upended the established order. Firstly, new technologies have made it possible to deliver increased output with smaller-cylinder engines, either turbocharged or not. Secondly, manufacturers have to contend with ever-stricter emissions standards.
Those new standards mean that automakers must produce vehicle fleets that consume less. Engines simply have to be less fuel-hungry. And that, naturally, requires relying more on 4-cylinder engines than V8s.
And so we come to the GMC’s new 4-cylinder turbo unit offered with its full-size Sierra truck. GM invited members of the automotive press to spend an afternoon getting acquainted with the new version, as well as a new trim that will be expanded across the model lineup, the Elevation.
Here’s how it went.
V8-type power
GMC’s new 2.7L 4-cylinder turbo engine comes standard in the SLE and Elevation trims of the Sierra for 2019. Peruse the specs sheet for it and you see many similar figures to a V8. Output, for example, is 310 hp and 348 lb-ft of torque.
The unit also gets GM’s Active Fuel Management (AFM) system, which means the engine can function on just two cylinders in certain situation, like when at cruising speed on a flat stretch of road. Stop/start technology is also present, which helps reduce fuel consumption when driving in the city. I’m happy to report it delivers smooth transitions, which isn’t always the case with this technology.
It all adds up to average fuel consumption of 12.6L/100 km city, 10.9L/100 km highway, when driving a front-wheel-drive model. A 4X4 iteration adds a few tenths to those figures. For our part, our test drive was too short to give an accurate reading, but on paper those numbers look to me both interesting (city) and disappointing (highway). In my experience, I’m used to getting results of between 11 and 12 litres per 100 km in similar circumstances when driving… a V8-equipped truck.
As for the towing capacity, it’s rated at 6,900 lb, which for the vast majority of owners is far more than they’re likely to need.
On the road
On paper is one thing, but how does the truck perform on the road? Here’s what I was able to learn in the short time GMC allotted us for our road test in a North American premiere.
The first question must regard power, of course, and in this respect there’s no need to worry. The output is easily sufficient, and the Sierra takes off like a rabbit when ordered to do so. During our excursion, we did note the 8-speed automatic transmission’s slightly odd, slightly annoying behaviour, and it felt to me as if we were dealing with a continuously variable transmission (CVT), from not just the sensations but the sounds we were getting as well.
Which isn’t great, to be honest. It’s particularly apparent when accelerating aggressively. When you tone it down, it’s less noticeable.
It was apparent enough that we sought more information about the transmission from the good folks at GMC. Here’s what Craig Couch, engineer at GM’s Oshawa plant, had to say:
GM’s explanation
“We use the same 8-speed transmission with the 5.3L V8 engine. Since the 4-cylinder engine is offered with base versions, we didn’t want to go with the 10-speed unit due to cost considerations. We preferred using the 8-speed to the 6-speed transmission, because it allows for smaller engine-RPM gaps between gears – which explains the CVT sensation. The 8-speed transmission also allows for quicker accelerations.”
Craig Couch added that big engine-RPM gaps have a negative impact on the linearity of the power output offered by the turbocharger, so having smaller gaps enables more-efficient delivery from that turbocharger. As well, he explained, the engineers went with a 3.42 differential in back instead of 3.23 in order to improve torque multiplication.
Craig Couch’s explanations did allow us to better understand the functioning of the transmission and the sensations we were getting from it. But that didn’t make it any more pleasant to deal with on the road. On the other hand, we’re more confident about its efficiency over the long haul.
A Sierra out to conquer
For the rest, the 2019 GMC Sierra is well-served by the new engine. The steering even felt a little light, which is a positive. When accelerating, the sounds you get are utterly atypical of what you’d expect from a pickup.
There are the kinds of qualities that will help it seduce new buyers and not so much target Sierra regulars. That’s the way GMC sees this product, and I tend to agree with them on this point. This is model out to make conquests
As for the Elevation variant, a trim level that will spread across the GMC lineup, it accounts for 22% f Sierra sales in Canada. This version is popular enough in fact that our market is getting exclusively a cabin crew iteration in this trim level.
As for pricing, the FWD version with twin cab sells for $45,700. When you climb to the 4x4 Crew Cab model, which is what we drove on the day, the price climbs to $51,200.
Conclusion
A full-size pickup powered by a 4-cylinder? The technology has progressed enough to make that a reality. The biggest hurdle may be the difficulty potential buyers have wrapping their heads around the idea, because in practice the engine does the job.
That said, when it comes to pulling really heavy stuff, nothing beats a good old V8. At least, until we see how far electric powertrains can go.
In any case, if you’re skeptical about the idea of a 4-cylinder in a truck, you’re not the buyer GMc is targeting with this variant.
Rather, this is a new weapon in GMC’s arsenal, one designed to expand its potential audience.
We’ll have to see how many it manages to seduce.
