Trucks & SUVs

The 2020 GMC Sierra Denali Is the Best Truck Only in Theory

Of all the candidates in the heavy-duty truck segment, which one is the best? If you look at the numbers, you might say the 2020 GMC Sierra Denali HD3500. It can tow up to 35,500 pounds and has a maximum payload of 7,442 pounds. Those specs are nearly impossible to beat.

But after comparing the Denali with the Ram Heavy Duty in both instrumented tests and real-world situations, the folks at MotorTrend have proven otherwise. We’ll find out why the Sierra Denali looks almost perfect on paper but also why the 2020 Ram HD won the honor of the 2020 MotorTrend Truck of the Year.

Engine differences between the 2020 Ram HD and the 2020 Sierra Denali

A 2020 GMC Sierra Denali on display at an auto show
The 2020 GMC Sierra Denali | Raymond Boyd/Getty Images

GMC offers two choices of engines in the Sierra 2500HD/3500HD. The gas version is a 6.6-liter V8 that produces 401 hp and 464 lb-ft of torque. It’s mated with a six-speed automatic transmission. The diesel version, which MotorTrend editors deemed the superior engine of the two, is also a 6.6-liter that delivers 445 hp and 910 lb-ft of torque. This engine is paired with a 10-speed Allison automatic.

In comparison, Ram gives buyers the choice of three engines in its heavy-duty trucks. The standard engine is a 6.4-liter Hemi V8 making 410 hp and 429 lb-ft of torque. It’s mated to an eight-speed automatic and has cylinder deactivation to kick in V4 mode for better fuel economy.

Then there is a 6.7-liter I6 Cummins twin-turbo diesel engine with a six-speed automatic. This diesel churns out 379 hp and 850 lb-ft of torque. A quantum step up from the other two engines is the Ram’s new high-output Cummins I6 with an Aisin-sourced six-speed automatic that is available only on the Ram 3500. The HO engine delivers 400 hp and a whopping 1,000 lb-ft of torque.

The differences between the two trucks’ engines became clearer when the
MotorTrend editors put the Ram and the 2020 Sierra Denali through both informal and instrumented tests.

Towing and hauling

The MotorTrend team used a Ram 3500 dually with the HO Cummins engine to tow a 20,000-pound gooseneck trailer and found it to be a stable trailering platform. This version of the 2020 Ram Heavy Duty in a regular cab style with rear-wheel drive and a Max Towing Package can tow up to 35,100, which is close to the Sierra’s towing capacity.

Although the Ram excelled in informal tests and was able to tow 17,730 pounds, the Sierra performed better overall on the proving ground and on punishing Davis Dam tests. The GMC had the advantage of four gears, 45 more hp, and 180 fewer pounds of curb weight.

At 7,680 pounds, payload capacity on the Ram 3500 slightly exceeds the 2020 Sierra Denali HD 3500. This capacity is rated on the Hemi engine version.

Ride quality

How a truck rides and handles is an aspect that can’t be measured objectively. But it’s here that the Ram HD truly outshines the Sierra. The
MotorTrend team noted that ride quality has been a chronic issue for heavy-duty trucks. And up until this model year, the Ram HD suffered from this problem until Ram Trucks used a multipronged approach to solve it.

One part of the solution is the addition of frequency response damping shocks that were first introduced on the 2019 Ram 1500. The valves on these shocks automatically adjust damping according to wheel input from road surfaces.

Multi-link suspension on the Ram 2500 and leaf-spring suspension on the 3500 work in tandem with the shocks to improve the trucks’ ride quality and handling whether empty or loaded. Buyers can also choose optional rear helper air springs that enhance the Ram’s ride even more.

The editors at MotorTrend felt that these updates help to make the Ram’s ride quality and handling is so much better than the Sierra’s. It felt more torquey, solid, and better damped. Even the Ram 2500 Power Wagon that the editors tested for offroading skills had a softer suspension, which had a better ride than other offroad trucks in its class.

And the Ram Limited’s ultra-luxurious cabin made its ride all that more comfortable, according to MotorTrend. In contrast, the Sierra Denali’s seats were hard and uncomfortable and its cabin layout was poorly designed.

The numbers vs. the real world

When they were deciding on which truck would win the Truck of the Year award, the MotorTrend editors had to take into account the whole truck. This included not just engine power, ride quality, towing and hauling capacities, and offroading capability but also fuel efficiency, safety, and value. 

The last factor, value, is another area where the 2020 Sierra Denali fell short as did the Ford F-350 Limited which ranked in a distant third place. The Ram 3500 Limited starts at $64,045, less than the GMC Sierra Denali HD 3500’s starting price of $67,895. The Ford F-350 Limited starts at an eye-watering $84,775.

The 2020 Ram 3500 Limited, while lagging slightly in towing and hauling capacities during formal testing, surpassed the Sierra Denali in all other categories for Truck of the Year. GMC may have to re-focus on ride quality, comfort and other more factors besides towing and hauling specs to make the Sierra Denali a stronger rival for Ram.