http://schema.org/NewCondition 2026 GMC 1GT4UPEY5TF103008 AT4

2026
GMC SIERRA 2500HD AT4 4X4 CREW CAB 8 FT. BOX (PDO)

Price

$118,909

118 909 $


Final Price

Price does not include taxes and licensing fees.

$118,909

Term (mo.)

Frequency

Price

$118,909

118 909 $


Final Price

Price does not include taxes and licensing fees.

$53,745

Finance For (2.99%)

$19.988 x 84 Months @ 6.49% APR (estimated financing rate, cost of borrowing $4,907).
Plus taxes and license.

$776 / mo

Term (mo.)

Frequency

Price

$118,909

118 909 $


Final Price

Price does not include taxes and licensing fees.

$53,745

Lease For (2.99%)

$19.988 x 84 Months @ 6.49% APR (estimated financing rate, cost of borrowing $4,907).
Plus taxes and license.

$776 / mo

Seaway Chevrolet Buick GMC Ltd

  Request Information  +1-844-937-1785

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Power Meets Precision: 2026 GMC Sierra 2500HD AT4 for Sale in Cornwall, Ontario

If you’re in the market for a heavy-duty truck that blends rugged off-road capability with premium refinement, the 2026 GMC Sierra 2500HD AT4 is your ultimate answer. Now available at Seaway GM in Cornwall, Ontario, this Crew Cab workhorse is designed to conquer Stormont, Dundas, Glengarry, and beyond with unmatched confidence and comfort. With intelligent technology, serious towing muscle, and a cabin that rivals luxury SUVs, the Sierra 2500HD AT4 redefines what a heavy-duty pickup can be.


Commanding Presence, Built for Eastern Ontario Roads

The 2026 Sierra 2500HD AT4 doesn’t just show up—it arrives with purpose. From its off-road suspension package with Rancho® shocks to its exclusive gloss-black 20-inch wheels wrapped in aggressive all-terrain tires, this truck is built to handle rural backroads, construction zones, and cottage drives with ease. LED projector headlamps and LED fog lamps light your path through early morning commutes or late-night hauls around Alexandria and Long Sault. With convenient assist steps and a 6.75 ft box, getting in, out, and on the job has never been easier.


Interior Comfort Meets Hard-Working Capability

Inside the AT4, you’ll find a bold Jet Black/Kalahari leather-trimmed cabin that fuses durability with refinement. Heated and ventilated front seats keep you comfortable in all seasons, whether you're hauling gear in Morrisburg or heading to the hockey rink in Maxville. A heated steering wheel and dual-zone automatic climate control make for a premium driving experience, while rear air vents ensure your passengers ride in comfort—no matter the season in Eastern Ontario.


Confidence-Boosting Safety & Technology You Can Trust

In the Sierra 2500HD AT4, GMC’s innovation shines through. With up to 14 available camera views including HD surround vision, you can confidently navigate tight job sites or trailering situations in Lancaster or Ingleside. Lane departure warning, OnStar safety services, and the ProGrade Trailering System deliver peace of mind whether you're cruising Highway 401 or backing into a dock at the marina. This is safety and tech built for people who use their truck like a tool—and expect more from it.


How It Stacks Up Against the Competition

Looking at rivals like the Ford F-250 Tremor or Ram 2500 Power Wagon? The Sierra 2500HD AT4 edges ahead with its integrated Google infotainment on a 13.4-inch touchscreen, wireless Apple CarPlay and Android Auto, and trailering-specific Adaptive Cruise Control. While others may offer brute force, GMC wraps its strength in smart technology and premium appointments—making it a more complete package for real truck owners in Cornwall and throughout SDG.


Why Buy from Seaway GM in Cornwall, Ontario

Seaway GM isn’t just Eastern Ontario’s largest GM dealer—it’s a community fixture with over three decades of experience. Founded by automotive veteran André Lapointe, our Cornwall dealership is your one-stop shop for Chevrolet, GMC, Buick, and Cadillac vehicles. From trade-ins and financing to genuine parts and certified service, we back every sale with real people, real expertise, and real commitment. Serving Cornwall, Ingleside, Lancaster, Alexandria, Morrisburg, and all communities in Stormont, Dundas and Glengarry, we're here for you every step of the way.


See Yourself in the Driver’s Seat

Picture yourself behind the wheel of this 2026 GMC Sierra 2500HD AT4, the premium heavy-duty truck that’s just as comfortable tackling rough jobs in Winchester as it is cruising into Cornwall on a weekend getaway. Whether you're towing a trailer through Martintown or exploring off-the-beaten-path with confidence, this is the truck built for your lifestyle. Reading about it is one thing—getting behind the wheel is when the real adventure begins.


Ready to Experience It in Person?

Schedule your test drive of the 2026 GMC Sierra 2500HD AT4 at Seaway GM today. Our team is ready to help you take the next step toward owning this exceptional truck. Book your appointment now and discover why this Sierra isn't just another heavy-duty pickup—it’s the best partner for life in Eastern Ontario.


Body Style: Pickup
Engine: 6.6L 8cyl
Mileage: 120 km
Exterior Colour: White
Interior Colour: Black
Fuel Type: Diesel
Transmission: Automatic
Drivetrain: 4x4
Stock #: 26069
VIN: 1GT4UPEY5TF103008
Trim Details: AT4 4x4 Crew Cab 8 ft. box

Axle RatiosMSRP
3.42 Rear Axle Ratio$00 $

Body
Pickup Box - Includes bed assist step.$00 $

Engine
Engine: Duramax 6.6L Turbo-Diesel V8 - B20-Diesel compatible. (Capped Fuel Fill, 220-Amp Alternator, Dual Heavy-Duty 70 Amp Battery (Includes 730 cold-cranking amps, maintenance-free with rundown protection and retained accessory power.), Winter Grille Cover, Exhaust Brake, Engine Block Heater, GVWR: 5,239 kgs (11,550 Lbs), 3.42 Rear Axle Ratio, Transmission: 10-Speed Automatic (MGM))$10,99510995 $

Engine Equipment
Engine Block Heater$195195 $
Dual 220-Amps Primary/170-Amps Aux Alternators$265265 $

Exterior Lamps
LED Smoked Amber Roof Marker Lamps$8585 $

Exterior Ornamentation
Black Front & Rear Moulded Splash Guards (LPO) - Dealer installed.$305305 $
Off-Road High Clearance Step (LPO) - Dealer installed.$1,6251625 $
Front License Plate Mount BC/MB/on - Included for vehicles shipped to British Columbia, Manitoba and Ontario.$00 $

Marketing Option Package
Preferred Equipment Group 4SB - (Engine: 6.6L V8 w/Direct Injection & VVT, Heavy-Duty 80 Amp Battery (Includes 720 cold-cranking amps, maintenance-free with rundown protection and retained accessory power.), GVWR: 5,012 kgs (11,050 Lbs), Transmission: 10-Speed Automatic, 3.73 Rear Axle Ratio, Front Bucket Seats, 10-Way Power Driver Seat Adjuster w/Lumbar, 10-Way Power Passenger Seat Adjuster w/Lumbar, Driver Memory (Recalls driver presets for power driver seat and outside mirrors.), Perforated Leather-Appointed Front Seat Trim, Wheels: 20" High Gloss Black 8 Spokes Aluminum ((50.8 cm).), Tires: LT275/65R20 AT BW, LT275/70R18 AT BW Spare Tire, Radio: AM/FM w/Premium GMC Infotainment System (Includes 13.4" diagonal multicolour touch-screen, Google built in apps such as navigation and voice assistance, multi-touch display, Bluetooth streaming audio for music and most phones; featuring wireless Android Auto and Apple CarPlay capability for compatible phones.), Sierra HD Pro Safety, Forward Collision Alert, Following Distance Indicator, Front Pedestrian Braking, IntelliBeam Automatic High Beam On/Off, Lane Departure Warning, Buckle to Drive (Prevents vehicle from being shifted out of park until driver seat belt is fastened; times out after 20 seconds and encourages seat belt use.), Automatic Emergency Braking, Safety Alert Seat, Rear Cross Traffic Alert, Trailer Side Blind Zone Alert, Wireless Phone Projection (For Apple CarPlay and Android Auto.), Bose Premium 7-Speaker Sound System (Includes Richbass woofer.), SiriusXM w/360L Trial Subscription (SiriusXM with 360L transforms your customers' ride with our most extensive and personalized radio experience on the road. Important: The SiriusXM trial subscription is not provided on vehicles that are ordered for Fleet Daily Rental (FDR) use. Certain features and/or content may not be available unless an active data connection is enabled in the vehicle. Content varies by SiriusXM subscription plan. Features and display may vary by vehicle. All SiriusXM services require a subscription, sold separately by SiriusXM after the trial period. Your SiriusXM service will automatically stop at the end of your trial unless you decide to subscribe. If you decide to continue service after your trial, the subscription plan you choose will continue for an indeterminate term and you will be charged according to your chosen payment method at the then-current rates unless and until you cancel. Taxes apply. Please see the SiriusXM customer agreement at siriusxm.ca/terms for complete terms and how to cancel, which includes calling SiriusXM at 1-888-539-7474. All rates, content, and programming are subject to change. SiriusXM uses personal information in accordance with SiriusXM privacy policy, available at siriusxm.ca/privacy. SiriusXM Canada Inc. (SiriusXM), the SiriusXM logo, channel names and logos are trademarks of Sirius XM Radio Inc. and are used under license.), Floor-Mounted Centre Console (Includes cup holders, cell phone storage, power cord management and hanging file folder capability.), Electric Rear-Window Defogger, Push Button Start, Remote Vehicle Starter System, Keyless Open & Start (Includes remote keyless entry.), Front Prem Floor Liners w/Removable Carpet Insert, Rear Prem Floor Liners w/Removable Carpet Insert, OnStar Services Capable (See onstar.ca for details and limitations. Services vary by model. Service plan required.), 120-Volt Instrument Panel Power Outlet (400 watts shared with (KC9) bed mounted power outlet.), 120-Volt Bed Mounted Power Outlet (400 watts shared with (KI4) instrument panel mounted power outlet.), 2 Charge-Only Rear USB Ports, 2 USB Ports (Located on 1st row console.), 2 Charge/Data USB Ports Inside Centre Console, HD Surround Vision (Provides the driver with an overhead view of the scene around the vehicle on a centre stack display. Includes front camera washer.), Bed View Camera w/2 Trailer Camera Provisions (Includes camera in the CHMSL to show a view of the cargo bed, display located in infotainment screen.), Trailer Cam Provisions & Trailer Viewing Software, Spray-on Pickup Bedliner w/GMC Logo (Does not include spray-on liner on tailgate due to black composite inner panel.), Heated Driver & Front Outboard Passenger Seats, Ventilated Driver & Front Passenger Seats, Heated 2nd Row Outboard Seats, Deep-Tinted Glass, Steering Wheel Audio Controls, Gloss Black Header Grille & Grille Insert Bars (Includes black chrome accents.), Manual Tilt-Wheel/Telescoping Steering Column, Unauthorized Entry Theft-Deterrent System, LED Cargo Area Lighting (Located in cargo bed activated with switch on centre switch bank or key fob.), Power Front Passenger Windows w/Express Up/Down, Wireless Charging, Ultrasonic Front & Rear Park Assist, Rear Wheelhouse Liners, Front Rain-Sensing Wipers, X31 Off-Road Package (Includes twin-tube Rancho shocks.), Off-Road Suspension (Includes twin-tube shocks.), Hill Descent Control, Skid Plates (Protect the oil pan, front axle and transfer case.), ProGrade Trailering System, Hitch Guidance w/Hitch View (Includes image adjustment and pan/zoom/tilt.), In-Vehicle Trailering System App (Includes checklist, trailer maintenance reminders, trailer security alerts, trailer mileage, tow/haul reminder, trailer electrical diagnostics and trailer tire pressure monitor system module. Includes trailer tire pressure monitoring alert when (PTT) trailer tire pressure monitoring sensors are installed.), 2-Speed Active Transfer Case (Electronic Autotrac with push button control.))$00 $

Option Group
Technology Package - (Inside Rearview Auto-Dimming Rear Camera Mirror (Includes full camera display.), Multicolour 15" Diagonal Head-Up Display)$1,5401540 $

AT4 Premium Plus Package - (AT4 Preferred Package, Universal Home Remote, Power Sliding Rear Window w/Defogger, LED Smoked Amber Roof Marker Lamps, Power Sunroof, Technology Package, Inside Rearview Auto-Dimming Rear Camera Mirror (Includes full camera display.), Multicolour 15" Diagonal Head-Up Display)$4,0054005 $
AT4 Preferred Package - (Universal Home Remote, Power Sliding Rear Window w/Defogger, LED Smoked Amber Roof Marker Lamps)$515515 $

Radio Equipment
3 Years SiriusXM - SiriusXM extended service subscription will stop at the end of the applicable subscription period unless you decide to continue service. Plan is non-transferable and non-refundable. Service subject to the SiriusXM customer agreement and privacy policy, visit siriusxm.ca/terms to see complete terms and how to cancel which includes online methods or calling 1-888-539-7474. Some services, content and features are subject to device capabilities, an active data connection enabled in the vehicle and location availability. All fees, content and features are subject to change. Content varies by subscription plan. SiriusXM and related logos are trademarks of Sirius XM Radio Inc. and its respective subsidiaries.$299299 $

Radio Type
Radio: AM/FM w/Premium GMC Infotainment System - Includes 13.4" diagonal multicolour touch-screen, Google built in apps such as navigation and voice assistance, multi-touch display, Bluetooth streaming audio for music and most phones; featuring wireless Android Auto and Apple CarPlay capability for compatible phones.$00 $

Seat Type
Front Bucket Seats - (10-Way Power Driver Seat Adjuster w/Lumbar, 10-Way Power Passenger Seat Adjuster w/Lumbar, Driver Memory (Recalls driver presets for power driver seat and outside mirrors.))$00 $

Sun/Moon Roof
Power Sunroof$1,3251325 $

Suspension Type
Off-Road Suspension - Includes twin-tube shocks.$00 $

Tire Type
Tires: LT275/65R20 AT BW - (LT275/70R18 AT BW Spare Tire)$00 $

Transmissions
Transmission: 10-Speed Automatic (MGM)$00 $

Wheel Type
Wheels: 20" High Gloss Black 8 Spokes Aluminum - (50.8 cm).$00 $

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Warranty Information Standard
Basic distance: 60,000 km
Basic months: 36 months
Basic warranty: 36 months/60,000km
Corrosion perforation warranty: 60 months/ unlimited distance
Drivetrain distance: 100,000 km
Drivetrain months: 60 months
Powertrain warranty: 60 months/100,000km
Roadside assistance coverage: 60 months/100,000km
Roadside distance: 100,000 km
Roadside months: 60 months

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* Every reasonable effort is made to ensure the accuracy of the information listed above. Vehicle pricing, incentives, options (including standard equipment), and technical specifications listed is for the 2026 GMC Sierra 2500HD AT4 4x4 Crew Cab 8 ft. box may not match the exact vehicle displayed. Please confirm with a sales representative the accuracy of this information.

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