What stood out to us on this 2020 Truck of the Year finalist
- Powerful diesel V-8
- Slick-shifting 10-speed
- Clever trailering cameras
- Half-assed gas V-8
- Cheap, unsightly interior
- Soft, squishy brakes
Think carefully before you check the option boxes—otherwise your GMC Sierra HD could be a dud. We sampled the gas and diesel engines at Truck of the Year, and although one was good and the other bad, both brought plenty of ugly.
Style is subjective, but most judges couldn’t look past the Sierra’s exterior design. Senior features editor Jonny Lieberman called Sierra HD’s fascia “grotesque,” and “drenched in jewelry. The bling-bling Ram HD looks restrained by comparison.” Indeed, the Great Wall of Chrome grille is extremely in-your-face.
Interior design is more objective for a truck like this. It needs to be a nice place to spend time on a long-haul drive. Unfortunately, it was more a place we wanted to get out of. “It isn’t even close to class competitive,” features editor Christian Seabaugh said, adding, “In a segment where Ram and Ford are bringing their A game, this phoned-in cabin leaves much to be desired.” Thin and hard seats, a dreadful layout, and a tiny infotainment touchscreen caught universal derision.
Guest judge Mark Williams was willing to trade those shortcomings for an all-new platform with more payload and towing capacity.”
The Sierra HD is available with a gasoline or diesel V-8, both displacing 6.6 liters. We also evaluated the gas unit and its six-speed automatic wrapped in the Chevrolet Silverado 2500 HD; it’s an identical driveline to the Sierra 2500 HD. In that installation, the 401-hp, 464-lb-ft engine doesn’t seem up to the task. MotorTrend en Español managing editor Miguel Cortina called it a “disappointment,” opining that it “feels too small for a truck of this size.” According to Seabaugh, it’s “gutless and inefficient” and “doesn’t feel like it makes more power than the 2.7-liter turbo I-4 in the Silverado 1500.”
Features editor Scott Evans was confused by the archaic automatic, questioning why this transmission still exists: “This old six-speed tends to hunt and isn’t clever about downshifting to maintain speed.”
Pulling a 10,500-pound (4,763-kg) trailer, things only got worse. Detroit editor Alisa Priddle asked, “Where did the power go?” Lieberman summed up our sentiment: “The big problem for all GM HDs is that this V-8 exists.”
Conversely, we praised the 445-hp, 910 lb-ft diesel V-8 and its 10-speed automatic transmission, which was tested in a dually Sierra 3500 HD. It’s the clear choice between the two powertrains—beyond comparison to its lower-grunt counterpart. Evans said it “has all the torque in the world, and this transmission handles it nicely.” Seabaugh agreed, appreciating how it felt “ridiculously powerful yet simultaneously unstressed.”
Road test editor Chris Walton welcomed the 3500 HD’s heftier steering over its 2500 HD counterpart, which made the task of keeping it centered in the lane easier. It handled a 10-ton trailer admirably, but Walton thought the exhaust brake didn’t do much if anything; manual gear selection was more effective for downhill speed control.
Stopping power left judges wanting more, worrying Cortina: “I really had to get on the brakes to get it to stop. It does, but I have to press hard on the pedal.” That’s a troubling evaluation for such a heavy chunk of steel. Still, the available camera array, which provides 15 different views around the truck and trailer, made piloting this beast easier.
Depending on the options selected, the GMC Sierra HD can disappoint as much as it impresses. We’d only consider the diesel, but with an unsightly interior and underpowered brakes it’s not a truck we’d ever love driving. Despite its mighty capabilities, other vehicles in the segment accomplish the same tasks with better overall execution. Check the boxes for those trucks instead.
|2020 GMC Sierra 3500HD Denali Duramax (CrewCab 4WD DRW)|
|Base Price/As Tested||$67,895/$80,805|
|Power (SAE net)||445 hp @ 2,800 rpm|
|Torque (SAE net)||910 lb-ft @ 1,600 rpm|
|Accel, 0-60 mph||6.9 sec|
|Accel, 0-60 mph (loaded)||Not tested|
|Accel, 0-60 mph (towing)||23.1 sec*|
|Quarter Mile||15.3 sec @ 89.8 mph|
|Quarter Mile (loaded)||Not tested|
|Quarter Mile (towing)||22.7 sec @ 59.7 mph*|
|Braking, 60-0 mph||134 ft|
|Braking, 60-0 mph (loaded)||Not tested|
|Double Lane Change Time||4.1 sec|
|Davis Dam Frustration||26.0 sec @ 1,830 ft**|
|Cruise Control 65-mph Overrun||5.3 mph|
|EPA City/Hwy/Comb||Exempt from testing|
|* NA-lb payload | ** 20,000-lb trailer|
|*** 35-55-mph uphill acceleration with 17,330-lb trailer|