2021 GMC Sierra 1500 in Alliston, ON

The 2021 GMC Sierra 1500 is a light-duty pickup truck that makes its case against a crowded segment as a gorgeous styled option that expertly balances engine performance selection, with innovative features from storage to tailgate to towing. Topped off by the iconic Denali model trim, the GMC Sierra is a pickup that looks good and backs it all up with supreme capability, and versatility to match wherever you need your truck to perform.

There’s a reason why we here at Ernie Dean Chevrolet Buick GMC consider ourselves as Truckville in Ontario, we have all the helpful answers to educate you on the perfect truck. A truck like this 2021 GMC Sierra 1500 can be found at our Alliston dealership, your one-stop destination for everything GMC pickups. Learn more about this legendary truck, and shop for one now, new or used, for sale in our extensive truck inventory!

Take a look here and browse the trim level differences, explore popular packages, or click here to take a look at the model pages for each specific trim: ElevationDenali

Browse comparison pages: Denali vs. 2021 Chevrolet Silverado 1500, Elevation vs. 2021 Chevrolet Silverado 1500 RST, AT4 vs. 2021 Chevrolet Silverado 1500 LT Trailboss

Explore the Heavy Duty Sierra here!

Exterior Design


Bold for any adventure in your path, the Sierra, SLE, Elevation& SLT Sierra 1500 trims boast gorgeous styling with incredible utility. Highlighted by these features:

  • 17-inch painted silver wheels
  • Chrome front & rear bumper
  • CornerStep rear bumper
  • Chrome grille surround with black mesh


  • 17-inch 6-spoke bright silver-painted aluminum wheels
  • Chrome front, rear bumpers
  • Cargo bed LED lighting
  • Heated power outside mirrors


  • 20-inch black gloss-painted aluminum wheels
  • Monochromatic exterior
  • Body-colour front, rear bumper
  • LED fog lamps


  • 18-inch 6-spoke aluminum wheels (with Dark Grey metallic accents)
  • Chrome front, rear bumper
  • Chrome grille surround (with high gloss black mesh, chrome inserts)
  • Heated, power, auto-dim driver-side folding outside mirrors

AT4: Durable & Refined

Ready for the roughest of terrain, while staying beautifully refined for showing off in the city, the AT4 is capable and distinguished, through and through.

  • Dark accents: Black chrome grille insert, fog lamp surrounds, body colour door handle and bumpers.
  • CarbonPro Edition: Features first use of carbon-fibre composite for a pickup bed, six-function MultiPro tailgate, 3.0L Duramax Turbo Diesel or 6.2L V8 engine available, exclusive exterior elements, 18-inch aluminum Dark Grey-accented wheels, with a 20-inch available.
  • 2-inch Factory Installed Suspension Lift: Exceptional ground clearance for off-roading.
  • Dual Exhaust Outlets: A seamless exhaust design that underlines its sophisticated style.
  • AT4 Off-Road Tires: Available 18- and 20-inch mud-terrain tires.

Denali Top-Level Design

For the top-level in Sierra 1500 style, appearance and capability, the Denali stands tall as the highlight of our GMC truck lineup.

  • Denali Premium Lighting: C-shaped LED headlights along with LED taillights and fog lamps create a premium lighting look, perfected with its light blade technology.
  • Signature Denali Elements: The Denali grille insert is finished in an unmistakable bright chrome, along with chrome vertical recovery hooks, door handles and mirror caps.
  • MultiPro Assist Steps: Available to allow seamless support into your pickup.
  • Bright Dual Exhaust Outlets: Fitting in effortlessly with the rear bumper, they help add to the Denali’s signature look.
  • Denali CarbonPro Edition: Available adding on the best of premium Denali elements.

Cargo Bed & Tailgate

The cargo bed and tailgate in the 2021 Sierra are incredibly innovative to provide the best and most versatile ways for you to easily store your cargo, and load it.

  • Hauling Utility: Durability in your truck bed is bred from the spray-in bedliner, high-strength roll-formed steel, 12 available cargo space, LED lighting, and better cargo volume than the competition.
  • MultiPro Audio System: Kicking back at your campsite? Tailgating before the game? Utilize the available MultiPro audio system that integrates with the tailgate to produce exceptional sound, complete with Bluetooth capability.
  • Rear Bumper Cornerstep: Footwells are found on both sides of the rear bumper, with textured grip that allows you to easily hop up with your boots.
  • MultiPro Tailgate: This isn’t your regular tailgate, with 6 different ways of opening and functioning to aid in loading, unloading and more.
Dimensions:Sierra 1500 Denali (Crew Cab, Short Box)Sierra 1500 Denali (Crew Cab, Standard Box)
Length (mm/in)5,886 / 231.76,128 / 241.3
Width (without mirrors) (mm/in)2,063 / 81.22,063 / 81.2
Height (mm/in)1,918 / 75.51,915 / 75.4
Wheelbase (mm/in)3,745 / 147.43,987 / 157.0
Cargo Box Length (on floor) (mm/in)1,776 / 69.92,018 / 79.4
Cargo Box Width (on floor) (mm/in)1,814 / 71.41,814 / 71.4
Tailgate Width (mm/in)1,814 / 71.41,814 / 71.4
Ground Clearance (mm/in)205 / 8.1205 / 8.1
Cargo Volume (L)1,7812,030
Curb Weight (kg/lbs)2,184 / 4,8152,208 / 4,867

Interior Design


The base level Sierra trim comes with a host of intuitive systems and design features inside the cabin. Including these highlights:

  • GMC infotainment system (complete with colour touchscreen)
  • Vinyl seat trim
  • 40/20/40 split-bench front seat
  • 60/40 split-fold bench rear seat
  • 4-way manual driver & front passenger seat


  • Cloth front 40/20/40 bench seat
  • Heated steering wheel/driver front passenger seat
  • Armrest and under-seat storage
  • Dual zone automatic climate control
  • Keyless open/remote start
  • Jet Black, Dark Walnut/Slate interior


  • Cloth front 40/20/40 bench seat
  • Heated steering wheel/driver front passenger seat
  • Armrest and under-seat storage
  • Available cloth front bucket seats
  • Jet Black interior


  • Available leather-appointed 10-way power adjust bucket seats
  • Heated second-row seats
  • Ventilated driver/front passenger seat
  • Jet Black and Dark Walnut/Slate interior
  • Heated driver/front passenger seats
  • 120-volt power outlet
  • Auto-dim rearview mirror

AT4 Sport Interior

The AT4 is the athletic trim of the Sierra 1500, highlighting the GMC trucks sporty elements through an interior that balances comfortability for any situation with a sumptuous look that is ready for top speeds.

  • 10-way power-adjust bucket seats
  • Heated, ventilated front leather seat surfaces
  • Jet Black interior, Kalahari accents
  • Dark-finished technical aluminum detailing
  • High quality front/rear floor liners, removable carpet inserts
  • AT4 badging on front headrests

Premium Denali Cabin

The most sophisticated Sierra you can enjoy, from off-roading to urban commuting, the Denali only represents the best in premium features.

  • 10-way power-adjust heated/ventilated front seats
  • Premium Forge perforated leather seat surfaces
  • Jet Black, Denali Dark Walnut/Dark Ash Grey interior
  • Open-pore real ash wood trim
  • Premium headrests, embroidered Denali logo
  • Premium carpet floor mats, available front/rear liners, available carpet inserts


It’s not just the incredible cargo bed that can take on your gear, the interior contains a versatile amount of spaces for all of your storage.

  • Seat storage: Rear seatback storage is available, with two compartments perfect for tablets and important devices.
  • Under-seat storage: Under-seat storage is available, perfect for sporting goods and tools.
  • Front storage: Centre console storage, along with a lockable console, lockable lower glovebox and upper glove box are perfect for your delicate items.
Dimensions:Sierra 1500 Denali Crew Cab
Front Headroom (mm/in)1,093 / 43.0
Rear Headroom (mm/in)1,019 / 40.1
Front Legroom (mm/in)1,131 / 44.5
Rear Legroom (mm/in)1,102 / 43.4
Front Shoulder Room (mm/in)1,677 / 66.0
Rear Shoulder Room (mm/in)1,655 / 65.2
Front Hip Room (mm/in)1,554 / 61.2
Rear Hip Room (mm/in)1,530 / 60.2
Passenger Capacity5

Performance & Capability

Engine Selection & Efficiency

There’s always a Sierra for you, especially with the 5 engines available, complete with exceptional power, efficient tech, innovative features and more to help you succeed wherever your ride finds you. The Dynamic Fuel Management System on the 5.3L V8 and 6.2L V8 allows the engine to operate through 17 different patterns, from 2 – 8 cylinders to provide the best power and efficiency needed. Speaking of efficiency, the 10-speed automatic transmission keeps you in the best range at all times, in accordance with your environment needs.

Diesel Technology

Powered by the DuraMax 3.0L Turbo-Diesel engine, with best-in-class 277 horsepower, 460 lb-ft of torque and primed for off-road performance, the diesel capability of the Sierra 1500 is both powerful and efficient. Start/stop tech and an engine block from light weight cast aluminum alloy keeps the system efficient, while the Active Thermal Management helps keep it at the perfect temperature.


On the 6.2L EcoTec3 V8 engine, enjoy the top level of 2021 GMC Sierra towing capacity at 5,352 kg (11,800 lbs). Along with its brawny capacity throughout the Sierra engines, there’s a multitude of trailer towing features to make your hauling easier than ever. The integrated trailer brake control allows for close-detail adjustment of your trailer brakes, trailer towing mirrors provide a generous view with heated, power-fold and auto-dim tech, and the electric parking brake assist helps you avoid roll and keep your set hitch ball alignment.

Specifications:4.3L Gas V62.7L Turbo5.3L EcoTec3 V86.2L EcoTec3 V8Duramax 3.0L Turbo-Diesel
Transmission6-speed automatic8-speed automatic10-speed, 8-speed, 6-speed automatic available10-speed automatic10-speed automatic
Torque (lb-ft)305348383460460
Fuel Efficiency (highway) (L/100 km) (2WD)15.1 / 11.511.9 / 10.314.0 / 10.1, 15.8 / 11.4--10.2 / 7.8
Fuel Efficiency (highway) (L/100 km) (4WD)15.8 / 11.913.0 / 11.4, 13.3 / 11.814.3 / 10.7, 14.7 / 11.2, 16.0 / 11.815.1 / 11.5, 15.7 / 12.410.6 / 9.2


GMC Infotainment System

This available system features an 8-inch touchscreen, your source for entertainment and navigation comfortably in your Sierra’s dashboard. Customizable presets mean any driver can automatically have their favourite settings saved for whoever is behind the wheel. It’s easily compatible with both your Apple and Android phone, and can even be used with its available 4G LTE Wi-Fi hotspot.

Apple CarPlay & Android Auto

Don’t worry about having to give up your phone when you sit behind the wheel, Apple CarPlay and Android Auto seamlessly connect your device to the infotainment system. This allows you to access your favourite apps, and doing so hands-free so you can focus on your drive and still enjoy your phone’s features, like music, messaging, calls and more.

Digital Diver Info Centre

There’s a lot going on in your Sierra, so have all of the important information positioned right in front of you with the available 8-inch Digital Driver Information Centre. In-between your vehicle gauges you’ll see such important info like trailer and safety alerts, to being able to monitor the Traction Selection System.


15 Camera Views

Keep another set of eyes on your truck and trailer at all times with the 15 different camera views available through the HD Surround Vision, Rear Camera MIrror and Bed View Camera. This multitude of views gives you a look where you previously never had before without getting out of your vehicle. This way you can keep hauling and keep tabs on everything happening outside.

Head-up Display

Available on the SLT, AT4 and Denali is the head-up display functionality, which projects your important info into a 15-inch display on your windshield. This allows you to keep your eyes on the road, while still being up-to-date on your driver information. Information like speed, tachometer, audio, navigation, fuel, hone safety alerts and the off-road inclinometer.

Advanced Safety & Driver Assist Tech

The Sierra is all about helping you out on the road. Along with its cameras that give you a better view, these driver assist features look out for you, notify you and act in small measures to deliver a safe ride. Adaptive Cruise Control keeps a selected gap between you and another vehicle, needing just you to steer, while Front and Rear Park Assist detects any objects around you, so you can nestle into the perfect parking space without any hassle.

What’s New From the 2020 GMC Sierra 1500?

If you’re interested in a GMC Sierra 1500, we know you’re going to want to tow. This is always front-of-mind for GMC, and why from the 2020 model the most notable upgrades into 2021 were upgrades to the trailer tech. This includes the Jack-Knife Alert, Trailer Length Indicator, improved Rear Trailer View and Rear Side View, along with Cargo Bed View with a zoom feature and Hitch Guidance. Adding on to the already impressive towing tech and features on the Sierra 1500, if you need a pickup for towing, the GMC Sierra is the truck for you.

2021 Sierra 1500 Model Trims

*Prices are for the 4WD Crew Cab, Standard Bed

2021 GMC Sierra 1500 base trim


Starting at $44,298*

Highlighted features:

  • Front, rear chrome bumper
  • StabiliTrak, with Traction Control
  • Hill Start Assist
  • GMC infotainment system
View Sierra Base Inventory
Front side view of 2021 GMC Sierra 1500 SLE, Elevation, SLT


Starting at $52,398*

Highlighted features:

  • Best-in-class Crew Cab front head/leg room
  • Better cargo bed volume than competition
  • LED headlights, C-shape signature
  • ProGrade Trailering system (available)


View SLE Inventory
Front side view of 2021 GMC Sierra 1500 SLE, Elevation, SLT


Starting at $55,698*

Highlighted features:

  • 3.0L Duramax Turbo Diesel engine (available)
  • Six-function MultiPro tailgate (available)
  • ProGrade Trailering system (available)
  • Better cargo bed volume than competition


View Elevation Inventory
Front side view of 2021 GMC Sierra 1500 SLE, Elevation, SLT


Starting at $60,298*

Highlighted features:

  • LED headlights
  • Six-function MultiPro tailgate (available)
  • Heated, leather-appointed front outboard seats
  • 15 available camera views
View Sierra 1500 Inventory
Front side view of 2021 GMC Sierra 1500 AT4


Starting at $66,998*

Highlighted features:

  • Exclusive Standard Continuous Damping Adaptive Ride Control
  • 15-inch diagonal Head-up Display (available)
  • Six-function MultiPro tailgate
  • Adaptive Cruise Control (available)
View AT4 Inventory
Front side view of 2021 GMC Sierra 1500 Denali


Starting at $69,998*

Highlighted features:

  • Exclusive Standard Continuous Damping Adaptive Ride Control
  • 15-inch diagonal Head-up Display (available)
  • Six-function MultiPro tailgate
  • Adaptive Cruise Control (available)
View Denali Inventory

From regular cab to crew cab, short box to long box, whatever your truck needs are, our Ernie Dean Chevrolet Buick GMC dealership here in Alliston has the answers and inventory to help you find what you’re looking for. Research your favourite pickup right from our site, build & price, finance and service all from our all-encompassing GM dealership. Have a question, or just want to experience the GMC Sierra for yourself in a test drive? Just ask and we’ll gladly help you out!

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