A white 2020 GMC Sierra 2500HD AT4 is parked in front of trees and a mountain.

GMC Sierra 2500 vs 3500 – Is Bigger Really Better?

When it comes to heavy-duty trucks, we often think that bigger automatically equates to “better.” A bigger truck means a bigger engine, a more massive vehicle, which in turn leads to bulkier payloads and a higher hauling limit, right? In most cases, that is entirely correct. But other than having the ability to tow and stow bigger and heavier loads, what advantages are there to owning a bigger truck? Let’s look at a couple of GMC trucks to answer this question.

The 2020 GMC Sierra HD is offered as 2500 and 3500 models, but how much of a difference is there between the two models? Both have been completely redesigned for 2020, so the buzz about these road beasts is high, along with expectations. And while both trucks deliver on the promises made by a new generation of heavy-duty trucks, many drivers are wondering whether they should bring home the 2500 or the 3500. It turns out there are several compelling arguments for each vehicle. From size, power, features, and more, the 2020 GMC Sierra HD 2500 and 3500 both offer a lot to love for drivers who need a trusted towing companion who can take on a variety of HD jobs without complaint.

The GMC Sierra 2500HD: Power

The 2020 Sierra 2500HD is the “little brother” in this equation; that is, if you can consider a vehicle with a curb weight ranging from 6,100 pounds to 6,900 pounds “little.” The 2500 has been designed to be big and strong, and its impressive height and aggressive stance alert everyone on the road that a powerful truck is coming through. Though it is a very large truck, the ride is comfortable and controlled, with a choice of two or four-wheel drive and a slew of trims, cab sizes, and bed dimensions. There are actually over 30 configurations of drivetrain, trim, cab, and bed size, including a regular cab, double cab, and crew cab, and long and standard bed. The trims offered are the base Sierra, SLE, SLT, AT4, and Denali. Note that the AT4 and Denali trims are available in four-wheel drive only.

From there, the next big decision is the engine type. As in, the engines themselves are massive. The first choice is a 6.6-liter gasoline V8. This engine offers 401 hp and 464 lb-ft of torque. Paired with a six-speed automatic transmission, this is a wise and commendable engine choice for those who need enough power and pull, but don’t quite need to max out. For those drivers, there’s a 6.6-liter turbodiesel V8, which offers 445 hp and an incredible 910 lb-ft of torque. This engine is joined with a 10-speed Allison automatic transmission.

A white 2020 GMC Sierra 2500HD AT4 is kicking up dirt on a dirt road.

2500HD Trims

Each trim provides the necessities, but as the trims climb, the features become more and more luxurious. On top of each trim, drivers can also choose to add optional packages to improve the comfort and convenience of your motorized work partner. The base Sierra trim, for example, includes Bluetooth connectivity, power windows, and power door locks, along with Apple CarPlay and Android Auto compatibility. Drivers can choose to add the Convenience Package on this trim to enjoy features like cruise control, keyless entry, rear window defogger, and LED lighting in the cargo bed.

The SLE trim makes life a bit easier with a color info screen, standard cruise control, leather-wrapped steering wheel, and WiFi hotspot, making it easier to stay connected regardless of where the job takes you. At this trim level, drivers can add a larger variety of optional packages, including the ProGrade Trailering system, which adds 15 trailer camera views, including the coveted trailer transparency view, allowing drivers to virtually see through their loads.

The SLT trim is a massive step up for those who plan to spend a large segment of their day in the company of their truck. Standard features include the ProGrade system and the MultiPro tailgate, which adjusts as needed to provide a step up, extra space, or a helping hand when loading and unloading. Also included on the SLT are power-adjustable front seats, dual-zone automatic climate control, and an 8-inch touchscreen infotainment system. SLT drivers can also modify their cabins with available front bucket seats and a center console with USB ports, adding more functionality to the on-road office concept.

AT4 models are the kings of the off-road, with lifted suspension, skid plates tow hooks, hill descent control, digital variable steering assist, Rancho twin-tube shocks, 12V power outlets, 120V power box, and power-adjustable front seats. Drivers can add the Preferred and Premium packages to AT4 to add more comforts, like a Bose audio system, roof marker lamps, and a navigation system, too. The top trim, and the executive office suite on the road, is the Denali. Premium leather heated, ventilated, and power-adjustable bucket seats with memory function set the stage for the most luxurious HD truck in GMC’s lineup. Everything is luxe on this model, from the sound system to the full suite of safety features, including lane change alert, blind zone alert, front, and rear park assist, perimeter lighting, IntelliBeam headlamps, and more.

A king among GMC trucks, a white 2020 GMC Sierra 3500HD Denali is towing a large camper along a lake-side highway.

The GMC Sierra 3500HD: Performance and Trims

In many ways, the 3500HD is similar to its smaller sibling. It comes in Sierra, SLE, SLT, AT4, and Denali trim levels, and while multiple cab/bed/trim combinations can be chosen, there are limitations. The SLT, AT4, and Denali are crew-cab only on the 3500 version. Long beds can be accompanied by single or double rear wheel configurations. The engine choices for the 3500HD are identical to those of the 2500HD, with the standard 6.6L gasoline V8, and an optional turbodiesel version. The horsepower and torque ratings do not change for the 3500HD, either.

The features are very similar, as well. The base trim, the Sierra, gets chrome on the outside, a 7-inch touchscreen display, and Bluetooth, Apple CarPlay, and Android Auto integration. The SLE trim includes a trailer brake controller and power convenience features, such as power windows, locks, remote keyless entry, and cruise control, along with OnStar and a WiFi hotspot.

The SLT includes the MultiPro tailgate, LED cargo bed lighting, 120V power outlets, leather upholstery, heated front seats, and remote engine starting, taking it up a notch. The AT4 version of the 3500HD is also made for off-roading, with its off-road tailored suspension, skid plates, all-terrain tires, locking rear differential, and standard four-wheel drive. It’s also equipped with a high definition surround-view camera system and an inclinometer, keeping things safe when taking a beast this size on the trails.

The Denali is again the top trim, with its premium Bose sound system, wireless device charging, larger infotainment system, parking sensors in front and rear, and a full application of Driver Alert safety technology, including Automatic Emergency Braking, Lane Departure Warning, Following Distance Indicator, and the vibrating Safety Alert Seat.

A low angle is shown of a black 2020 GMC Sierra 3500HD Denali that is towing construction equipment.

So What’s the Difference?

So far, all of the details look pretty similar. The engines are the same. The features are essentially identical, though there are a few deviations in availability. Both vehicles have virtually the same head and legroom when comparing the same cab and trim across the pair.

The primary difference is in the power. When properly equipped, the 2500HD can tow a maximum of 18,500 pounds. Not too shabby, until you consider that the redesign of the 3500HD allows it to pull a gooseneck load up to 35,500 pounds. While the 2019 3500HD maxed out at 23,100 pounds, GMC’s updates to the Sierra allow for greater pull than ever before. Along with that is the payload. A 2500HD can comfortably take on loads under 3500 pounds. A regular cab dually 3500HD has the guts to carry up to 6,500 pounds.

If you need a truck that can pull, carry, tow, and stow a lot, there’s no comparison between the 2500 and the 3500. However, if you need something with a little more maneuverability, that can take care of itself on city streets, you might consider the 2020 GMC Sierra 2500HD. This version is a little slimmer and has the ability to wiggle in and out of tight spots with more proficiency than its big brother. It’s also going to carry the smaller price tag out of the two, which can be a huge deciding factor.

So is bigger better? In terms of hauling and towing, yes. The 2020 GMC Sierra 3500HD is far superior when it comes to taking on heavy loads. But when it comes to carrying passengers, having room for your stuff, and adding in all the comforts that make your truck your home or office on the road, both vehicles, large and small, have plenty to offer.