2020 GMC Sierra Heavy Duty First Drive - Tow Happy

Tim Healey
by Tim Healey

Heavy-duty truck buyers tow things often. So do many light-duty truck buyers. So perhaps I shouldn’t have been surprised to be be asked, shortly after stepping off an airplane, to get behind the wheel of an HD truck towing something like 13,000 pounds of RV.

This, despite having trailering experience that hovered near zero. I can count on one hand how many times I’ve trailered. I did it years ago in Maryland on another GMC event, and last year in the same region (Jackson Hole, Wyoming) with the light-duty Chevrolet Silverado, but until last week, that was about it.


GMC would tell you that the combination of its trucks’ capability and some high-tech doodads make trailering easy, even for the novice. GMC would be correct on that count, but there’s more to the story when it comes to this year’s crop of trucks.

We were turned loose in a variety of GMC Sierra trucks over the course of two days – and not all had a mobile home’s worth of weight behind them. Still, towing and hauling were a bit part of this particular junket; even when we weren’t towing, we were driving trucks with beds full of logs. We also did a bit of light off-roading.

(Full disclosure: GMC flew me to Wyoming and housed me and fed me so that I could drive these trucks and the updated Acadia AT4).

GMC’s HD trucks are heavily updated for 2020, with most highlights pertaining to trailering. The truck has also grown taller and wider, with a longer wheelbase and larger grille than before. The cabin is updated, too.

There’s powertrain news, too, in the form of a new 6.6-liter gas V8 that makes 401 horsepower and 464 lb-ft of torque. That goes along with the venerable 6.6-liter Duramax turbodiesel that makes 445 horsepower and 910 lb-ft of torque. The gasser mates to a six-speed automatic transmission, while the oil-burner pairs with a new 10-speed automatic.

The four-wheel-drive system is new, offering a full-time 4-hi automatic setting. That’s a first for a heavy-duty Sierra.

As might be expected, the diesel is up to the task when it comes to towing. Even at altitude, the diesel got the job done without drama. You’re never going to accelerate quickly with 13,000 pounds back there, nor should you want to, but the diesel worked almost effortlessly, even when ascending grades. And the exhaust brake kept any judder and shake during coasting or braking to a minimum.

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Even for a rook like me, the towing was easy-peasy.

It’s not just the engine or the 10-speed that helped. GMC’s biggest selling point in this class may be its trailering and camera apps. The system is so in-depth that I only have space (even in the virtual world) to just scratch the surface.

Here’s one fun thing you can do: You can use the cameras to get a virtual “see through” view (just one of 15 available views from the eight cameras, although this one while require you to add an accessory camera to the trailer) of the trailer behind you. That’s right – the trailer won’t block your view. You’ll be able to see what’s behind you, thanks to the magic of technology. You can also use cameras to see inside the trailer, to make sure no vagrant with bad intent is hiding back there. Or more likely, to make sure your cargo is in the right place. There’s also turn-signal-activated cameras to help with urban maneuvering.

There’s also a rearview-mirror camera, which provides a sharp image but doesn’t perform any other trickery.

The trailering app can let you do things like check trailer lighting, monitor trailer tire pressure, and run trailer electrical diagnostics. Some of this can be done via your phone, as well, provided you download GMC’s app.

Laden or not, the Sierra HD handles like the big truck it is. It rides well, and gentle curves won’t disturb it, but hey, it’s still a truck. Acceleration from an unladen diesel is around-town acceptable, even at altitude.

The same goes for the 6.6-liter gas powerplant – I drove it without a trailer attached, but with a large payload of logs in the back, and found it fine for the gentle cruising we were doing.

Another cool feature is the MultiPro tailgate, which lets you use it in different configurations, and it can even hide an available speaker. Those commercials for the tailgate may be annoying, but it does neat tricks and it may be a killer selling point for some customers.

The upgraded styling includes a functional hood scoop. Mostly, the look is simply more “In your face” than before, partly thanks to the truck’s growth in size. The grille almost gives off a semi-truck vibe. Almost.

Inside, it’s a letdown. The interior is functional enough for ease of use, and the overall design is far from ugly, but like with the Silverado light-duty trucks I drove last year, the Sierra immediately reads as outdated when compared to Ford and Ram’s offerings. Not to mention that our early production test trucks suffered from remarkably large panel gaps and in one case, a trim piece was loose.

Sure, it’s quiet in the cabin, even with a lot of weight rolling out back, and the aforementioned camera and trailer apps are easy to use (and easy to learn quickly). And yes, the seats are comfortable, and there’s plenty of space for humans. There’s also lots of storage for small stuff.

But there’s no pizazz here. A light-duty Ram, properly equipped, can dazzle the eye. Ford’s interior design is a bit weirder to me, but at least there’s an effort to stand out. Here, the only reminders that its 2019 and not, say, 2010 are the presence of an available wireless cell-phone charger and the apps, including Apple CarPlay and Android Auto.

It’s not just a design issue – the materials felt cheap for a truck that’s priced well into Corvette territory. This was especially glaring on the Denali models. GMC prides itself on being an upscale brand, and Denalis are supposed to feel special – but these interiors don’t. Why even spring for the GMC over the Chevy?

And I do mean spring. I drove several different trucks, and depending on how one chooses to option his or her rig, the pricing can get a bit eye-popping. One Denali rig I tested checked in at $81,705 – and that was after a discount. The cheapest truck I tested was in the mid-60s with options.

Standard and available features, depending on trim and configuration, include hill-start assist, ProGrade trailering system, MultiPro tailgate, infotainment, navigation, Bluetooth, in-truck Wi-Fi, Apple CarPlay, Android Auto, premium audio, keyless entry, remote start, wireless cell-phone charging, cooled front seats, heated front and rear (outboard) seats, heated steering wheel, fog lamps, forward-collision alert, lane-departure warning, lane-change alert with side blind-zone alert, rear-cross traffic alert, sunroof, rear camera mirror, bed camera, head-up display, safety alert seat, and automatic emergency braking.

Available wheel sizes include 17, 18, or 20 inches. Max towing is listed at 35,500 pounds.

These are perfectly capable trucks with stout engines that can tow huge rigs. The trailering apps make towing easy for novice and veteran alike, and will be a strong selling point. As will the MultiPro tailgate. These rigs are also smooth, quiet, and comfortable – a long drive is no chore in these trucks. Even the handling isn’t all that objectionable – it’s truck-like, to be sure, but pleasant enough.

But as I said about the Silverado last year – is fine good enough? Truck buyers are extremely loyal, and that may work in GMC’s favor on the one hand, because the loyal buyer isn’t gonna give a whit about the flaws. On the other hand, it will be hard to conquest Ram and Ford buyers when the interior bits aren’t up to snuff. Not to mention that “first truck” buyer – is the retiree who needs to haul an RV going to be so dazzled by the trailering apps that he or she would prefer to spend a good chunk of their savings on the Sierra instead of the Ram?

I am related to GM truck loyalists. Those who have an affinity for the company and will continue to buy Chevys or GMCs every time their old rig is ready for the junkyard will appreciate these trucks – they can do what their owners ask, no sweat. But does GM want to settle for simply keeping its existing customer base happy?

There’s cool innovation here – the trailering and camera apps really did impress me. And I dig the MultiPro tailgate. That said, there’s no reason GMC should be using downmarket materials on a truck at this price point (even a heavy-duty one), and while one or two panel gaps or broken trim pieces can be excused on early builds, I saw lackluster build quality in each truck I drove.

With a modernized interior and better build quality, the Sierra HD would be right there with the Ram and Ford in the battle for truck supremacy. As of now, it’s a very capable truck with masculine exterior styling and cool features that is let down by a couple of major flaws.

[Images: © 2019 Tim Healey/TTAC]

Tim Healey
Tim Healey

Tim Healey grew up around the auto-parts business and has always had a love for cars — his parents joke his first word was “‘Vette”. Despite this, he wanted to pursue a career in sports writing but he ended up falling semi-accidentally into the automotive-journalism industry, first at Consumer Guide Automotive and later at Web2Carz.com. He also worked as an industry analyst at Mintel Group and freelanced for About.com, CarFax, Vehix.com, High Gear Media, Torque News, FutureCar.com, Cars.com, among others, and of course Vertical Scope sites such as AutoGuide.com, Off-Road.com, and HybridCars.com. He’s an urbanite and as such, doesn’t need a daily driver, but if he had one, it would be compact, sporty, and have a manual transmission.

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9 of 16 comments
  • Dal20402 Dal20402 on Aug 29, 2019

    Really too bad they screwed up the interior execution and the front-end styling so badly. These seem like decent trucks except for those two big problems.

    • SSJeep SSJeep on Sep 10, 2019

      I like the front end of the GMC. But the interiors are loathsome in the segment, especially at the price point. I am in the market for a new truck - but that interior would be hard to deal with on a daily basis...

  • Alcolawl Alcolawl on Aug 29, 2019

    Can anyone tell me why they're ditching the 6.2L V8 for a 6.6L V8 that creates less horsepower and the same amount of torque a whopping 100 RPM sooner? Perhaps it's underrated? Genuinely curious.

    • See 5 previous
    • Jon Jon on Aug 30, 2019

      @ajla I sit corrected

  • MaintenanceCosts I hope they make it. The R1 series are a genuinely innovative, appealing product, and the smaller ones look that way too from the early information.
  • MaintenanceCosts Me commenting on this topic would be exactly as well-informed as many of our overcaffeinated BEV comments, so I'll just sit here and watch.
  • SCE to AUX This year is indeed key for them, but it's worth mentioning that Rivian is actually meeting its sales and production forecasts.
  • Kjhkjlhkjhkljh kljhjkhjklhkjh a consideration should be tread gap and depth. had wildpeaks on 17 inch rims .. but they only had 14 mm depth and tread gap measured on truck was not enough to put my pinky into. they would gum up unless you spun the libing F$$k out of them. My new Miky's have 19mm depth and i can put my entire index finger in the tread gap and the cut outs are stupid huge. so far the Miky baja boss ATs are handing sand and mud snow here in oregon on trails way better than the WPs and dont require me to redline it to keep moving forward and have never gummed up yet
  • Kjhkjlhkjhkljh kljhjkhjklhkjh Market saturation .. nothing more