Search Cars for Sale

2021 GMC Sierra 1500 Review

The 2021 GMC Sierra 1500 is a competitive and alluring player in the full-size truck segment. Just off a complete revamp two years ago, the Sierra still feels quite fresh. The Sierra is the General Motors sibling to the Chevrolet Silverado, and while they share powertrain options and other features, the GMC Sierra stands out with its own styling and “professional grade” attitude.

Like its rivals the Ram 1500 and Ford F-150, the GMC Sierra is available in a wide range of forms and cab/bed configurations to suit a variety of needs. On one end it can be had as a pretty basic work truck, while on the other there’s the Denali trim that’s more akin to a luxury vehicle. Engines range from the GM’s venerable V8s to a turbocharged 4-cylinder and a stout 6-cylinder turbodiesel.

The GMC Sierra offers its innovative MultiPro Tailgate, impressive trailering camera system and gets some technology upgrades for 2021. Both can only help in this competitive segment against the tech-laden Ram 1500 and all-new 2021 Ford F-150.

What’s New?

For 2021, the GMC Sierra 1500 is updated with available wireless Apple CarPlay and Android Auto, the option of active safety features such as automatic emergency braking on base models, and more trailering assists such as jack-knife alert and trailer length indicator. Also, tow ratings have increased for the Sierra’s diesel inline-6 and turbocharged 4-cylinder engines. See the 2021 GMC Sierra models for sale near you

What We Like

  • MultiPro tailgate
  • ProGrade trailering system
  • Range of engine choices
  • User-friendly infotainment system
  • Available carbon fiber bed
  • Smooth ride, especially with optional Adaptive Ride Control
  • Luxurious Denali model

What We Don’t

  • Interior is still too similar to the Silverado
  • Arguably overpriced in the higher trims when compared to competitors
  • Outclassed in interior luxury by some rivals
  • Lags rivals in power output and towing figures

How Much?

$29,700-$59,000 (before options and not including $1,595 destination charge)

Fuel Economy

The most efficient version of the gasoline-fueled Sierras is the rear-wheel-drive (RWD) 2.7-liter turbo 4-cylinder truck with its 8-speed automatic transmission. It achieves a government-estimated fuel economy of 20 miles per gallon in the city, 23 mpg on the highway and 21 mpg combined. Opting for four-wheel drive (4WD) lowers those numbers to 18 mpg city/21 mpg hwy/19 mpg combined. It delivers 310 horsepower and 348 lb-ft of torque.

The base 4.3-liter V6 with its 6-speed automatic transmission makes 285 hp and 305 lb-ft. It delivers 16 mpg city/21 mpg hwy/17 mpg combined in RWD form, while 4WD V6 models earn 15 mpg city/20 mpg hwy/17 mpg combined.

Most buyers will gravitate toward GM’s 5.3-liter V8 generates 355 hp and 383 lb-ft of torque. In the Sierra it is available with three different automatic transmissions. RWD models with a 6-speed automatic earn 15 mpg city/21 mpg hwy 17 mpg combined, while 4WD models earn 15 mpg city/20 mpg hwy/17 mpg combined. Models with the 5.3-liter V8 and 8-speed automatic earn 17 mpg city/23 mpg hwy/19 mpg combined with RWD and 16 mpg city/21 mpg hwy/18 mpg combined with 4WD. Finally, 5.3-liter V8 models with a 10-speed transmission – available only with 4WD – earn 16 mpg city/22 mpg hwy/19 mpg combined and 16 mpg city/21 mpg hwy/18 mpg with the off-road AT4 trim.

The 420 hp 6.2-liter V8 creates 460 lb-ft of torque. It’s only offered with 4WD and provides up to 16 mpg city/20 mpg hwy/17 mpg combined. In AT4 trim, those numbers are lowered to 15 mpg city/19 mpg hwy/17 mpg combined.

The most efficient 2021 Sierra are those with the inline-6 turbodiesel that makes 277 hp and 460 lb-ft of torque. In RWD form they earn an impressive 23 mpg city/30 mpg hwy/26 mpg combined. With 4WD the diesel Sierra earns 22 mpg city/26 mpg hwy/24 mpg combined.

Standard Features & Options

Despite being marketed as a premium truck, there aren’t an overwhelming number of bells and whistles standard on the base model of the Sierra 1500 because it’s still, after all, a work truck at heart. You will pay extra for any exterior color other than white. Paint prices begin at $195 for red up to $595 for what GMC labels Red Quartz Tintcoat. Prices exclude the $1,595 factory destination charge.

Standard on the base Sierra ($29,700) are LED headlights and taillights, an illuminated cargo bed, rear corner steps, a 7-in infotainment system with Bluetooth, Android Auto and Apple CarPlay. You also get one USB port. Other than that, it’s a pretty bare-bones work truck. At its most basic in regular cab/long bed form, it doesn’t even have power windows or door locks (though you do these those basic features with double cab or crew cab models). Note also that adjustments are limited to a 4-way manual driver’s seat and tilt-only steering wheel.

In addition to opting for a V8 instead of the base V6, you can add power windows, keyless entry, cruise control, and active safety features like forward-collision warning with automatic emergency braking.

Moving up to the SLE trim ($40,400) gives you a much nicer truck. The base engine becomes the 2.7-liter turbo-four. It can only be had in double cab or crew cab configurations. With it comes 10-way power-adjust driver’s seat, dual-zone climate control, leather-wrapped steering wheel, cruise control, heated front seats, remote start and 4G LTE integration with Wi-Fi. It also has silver-painted 17-in aluminum wheels and automatic locking rear differential. The 3.0-liter Duramax turbodiesel 6-cylinder is now available starting on this trim.

Next up is the Elevation trim ($42,100), which puts a sporty spin on this rugged truck. It has a monochromatic appearance package with a big, black grille, LED fog lamps and body-color painted bumpers plus 20-in black rims. In terms of standard and available features, the Elevation model is similar to the SLE.

Upgrading to the Sierra SLT ($47,000) is where things really start to get fancy. The standard engine is the 5.3-liter V8 with DFM and it’s where the MultiPro tailgate becomes available. It also adds an 8-inch touchscreen display, high-intensity lighting, a traction select system and the ProGrade trailering system, which includes Hitch Guidance with a Hitch View rear camera, auto electric parking brake assist and a tailgate-mounted light for easy nighttime trailer hook-ups. There’s also a handy trailering app in the Sierra’s infotainment system. On the SLT model, you also get an integrated trailer brake controller, leather seats that are heated and power-adjustable in front and a heated steering wheel. Newly standard for 2021 is wireless Apple CarPlay and Android Auto. Truck shoppers looking for a satisfying blend of luxury, capability, technology and value should take a close look at the Sierra SLT.

The next step up the Sierra food chain is the AT4 ($53,800). GMC’s AT4 models are geared toward off-road enthusiasts and outdoor adventurists. However, don’t expect Ford F-150 Raptor levels of off-road capability. The Sierra AT4 comes with standard 4WD, the MultiPro tailgate, a 2-in lift kit, an AutoTrac 2-speed transfer case, Rancho off-road suspension and skid plates, an automatic locking rear differential, black leather seats with Kalahari accents (an AT4 exclusive), heated and ventilated front seats, and heated rear outboard seats. The appearance package includes red vertical recovery hooks and a black chrome grille and accents.

GMC’s CarbonPro carbon-fiber bed is available beginning on the AT4 trim.

Finally, we’ve reached the summit of GMC pickup excellence: the Denali ($55,200). This high-end pickup comes with perforated Forge leather seating and open-pore ash wood trim, making for premium materials you might be surprised to find in a truck. Of course, the seats are heated and ventilated in front and heated in back, plus you get an 8-in digital driver information center in the dash, Bose premium audio, lane-change assist with side blind zone alert, rear cross-traffic alert, safety alert seat and even more safety tech. This model also includes the sophisticated Adaptive Ride Control suspension. Available tech in the Denali includes a 15-in head-up display, a surround-vision camera, a rear camera mirror, MultiPro power steps and adaptive cruise control. On the outside, you get a signature Denali grille with high-gloss black mesh and chrome inserts, plus plenty of Denali badging inside and out. The Sierra Denali has a gorgeous interior, but it has a tough competitor in the likes of the high-end Ram 1500 models, which are available with similar premium materials and a massive 12-in infotainment system.

There are all manner of options and option packages in numbers too many to itemize here.


The 2020 Sierra 1500 earned pretty good marks from the Insurance Institute for Highway Safety, getting a Good rating in most categories but only a Marginal rating for passenger-side small-overlap front crash test. It gets a Poor rating for headlights but a Superior rating for crash avoidance and mitigation with optional equipment. In federal NHTSA testing, it receives four stars out of five. Some, but not all, 2020 models of the Ford F-150 and Ram 1500 earned five stars.

The 2021 Sierra offers active safety systems, and new this year is the Safety Confidence Package available on base models that includes forward-collision alert with pedestrian detection and automatic emergency braking. Also available is the Driver Alert Package I with front and rear park assist and blind-spot monitoring.

The Driver Alert Package II available starting on the SLE trims has adaptive cruise control and GM’s IntelliBeam automatic high-beam control.

Behind the Wheel

One of the first things we noticed when we spent some time behind the wheel of last year’s Sierra is just how smooth and comfortable it is. It’s not hard to see why trucks are so popular, even for folks who might not necessarily need their muscular capabilities that often. Regardless of the payload you’re carrying or the load that you’re towing, if any at all, the Sierra is just a nice highway cruiser, especially the Denali model equipped with Adaptive Ride Control, which makes it even smoother on the highway but doesn’t make all that much of a difference in city driving.

The MultiPro tailgate might seem gimmicky, but we are big fans of it. We think its many functions can actually save you a lot of time for specific hauling purposes like long items that require load stops. It also makes it a breeze to climb in and out of the bed and easier to reach your cargo. We even found the desk feature to be useful for setting a laptop on and getting some work done. The MultiPro tailgate isn’t an absolute necessity, but it’s a worthwhile upgrade if you’re planning on doing a lot of hauling.

Mechanically speaking, we have few complaints about the tried and true V8 engines available under the hood of the Sierra. We like the fuel economy of the 5.3-liter and we like the muscle of the 6.2-liter. The turbo-four is surprisingly peppy and makes this large truck feel lighter on its feet. The V6 is good enough for the base model, but we’re not too upset about it not being available in most trims. Then there is the turbodiesel with its monster torque and 30 mpg on the highway. This engine is an excellent powertrain, giving this half-ton truck the grunt usually associated with heavy duty trucks and great efficiency. It’s also pretty quiet for a diesel.

The age-old problem of hooking up a trailer being a pain in the neck, especially by yourself, has been largely remedied by GMC, which is saying a lot. The upgraded optional ProGrade trailering system is a must for anyone who does a lot of trailering and doesn’t always have the luxury of someone to wave their arms around behind you, indicating how close you are to your target while hooking up the trailer. Having that camera showing exactly where you need to put the truck plus the safety benefit of auto braking assist make for a much-improved trailer hook-up experience that we think is worth the cost.

Moreover, the platoon of cameras that work in harmony to provide many different viewpoints, including the remarkable “transparent trailer” view that nearly makes child’s play of towing a big load. It really allows the driver to keep track of what is going behind the trailer as well as along its flanks. For 2021, this technology is further improved with jack-knife alert for compatible trailers and trailer length indicator, which displays a red overlay twice the length of the trailer on the console screen when changing lanes.

As for towing, the max capacity varies with each engine. For 2021, the turbodiesel is rated to pull up to 9,300 pounds. The turbocharged 4-cylinder is now rated to pull up to 9,200 pounds. At its max, the 2021 Sierra is rated to tow up to 11,800 pounds. That’s impressive but trails the Ram 1500’s 12,750-pound max. And Ford has announced the 2021 F-150 will tow up to 14,000 pounds.

Other Cars to Consider

2021 Ford F-150 – Ford’s best-seller is all-new 2021 and it packs the latest technology, more performance, innovative powertrains with on-board generators, and a hybrid model with 430 horsepower and 570 lb-ft of torque.

2021 Ram 1500Ram’s half-ton truck also boasts impressive levels of technology and creature comforts.  It’s available with 3.0-liter turbodiesel V6 and, new for 2021, the insane Ram TRX with 702 horsepower.

2021 Chevrolet Silverado – GMC’s sibling, the Chevy offers similar powertrains and features, but its own looks and brand image.

Used GMC Sierra – This generation of Sierra trucks debuted in 2019. If you pick up a model that’s a couple years old you’ll still get many of its great features and can save several thousand dollars.

Questions You May Ask

Is GMC Sierra SLE or SLT better?

The 2021 GMC Sierra SLT is the higher trim and has more features. Among them are the MultiPro tailgate, power driver’s seat, 8-inch screen and more.

What is the difference between the GMC Sierra and Chevrolet Silverado?

Both brands fall are part of General Motors, and each truck offers similar powertrains and other functions. Their differences lie in design, brand image, and trims, such as the off-road oriented Sierra AT4?

Is the GMC Sierra a good truck?

Yes, the Sierra is recommendable for its wide variety of powertrains and configurations. However, the Ram 1500 has more in-cabin technology, and the 2021 Ford F-150 is all new and offers a powerful hybrid model. Both trucks also out-tow the Sierra.

What is the difference between the 2020 Sierra and 2021 Sierra?

The 2021 model gets new features like wireless Apple CarPlay/Android Auto, more trailer technology, and more options available on lower trims.

Autotrader’s Advice

The GMC Sierra 1500 has a broad range of trims, lineups and configurations. That variety is a blessing in terms of fitting the needs for a broad range of buyers, but it can be perplexing if you’re still indecisive. Don’t fret, however. We think the Sierra’s sweet spot is in the SLT model, which gives you the cool MultiPro tailgate, a leather-trimmed interior, the ProGrade trailering tech and a great V8 engine in the mid-$40k range. That makes it a strong value for most truck shoppers. Of course, if you have the dough, a Sierra Denali is a great choice with premium amenities. And if you desire a bolder, tougher-looking, higher-riding and more off-road capable Sierra, the AT4 delivers. No matter which one you go with, you’re getting a classy, modern, high-tech truck in the 2021 GMC Sierra 1500. Find a GMC Sierra 1500 for sale


Matt Degen
Matt Degen
Matt Degen is an author specializing in interesting news and features about cars. Matt is a longtime lover of both cars and news, as well as the latest technology. He was the past automotive editor of The Orange County Register newspaper and a former board member of the Motor Press Guild, the nation’s largest automotive media association. He holds degrees in Communications and Culinary Arts.... Read More about Matt Degen

Sign up for Autotrader newsletters

The best cars and best deals delivered to your inbox

Email Address 

By subscribing, you agree to our privacy policy

Where You Can Buy

Loading dealers...

Leave a Comment

Most Popular Articles

2020 Hyundai Sonata Hybrid: First Look

The 2020 Hyundai Sonata Hybrid jumps to the head of the hybrid class.

Best Truck Deals: August 2022

These are the best deals on trucks for the month of August 2022.

Mazda Goes Off-Road With New CX-50 SUV

Mazda takes a new road with its new CX-50 -- an unpaved one, at that.

Search By Style

More Articles Like This