2025 GMC Sierra 1500 AT4 vs 2026 GMC Sierra 1500 AT4
These two are closer than you would think. The data shows minimal separation. Key numbers: $200 price gap, 305 vs 305 hp, 24 vs 24 MPG.
The spec table compares 0 specifications head to head.
What's Actually Different
These two vehicles differ in 0 specifications.
Full Specification Comparison
Specifications and pricing reflect available data as of early 2026 and may not match current manufacturer figures. Always confirm details with an authorized dealer before making a purchase decision.
| Spec | 2025 GMC Sierra 1500 AT4 | 2026 GMC Sierra 1500 AT4 |
|---|---|---|
| Pricing | ||
| MSRP | $66,800 | $67,000 |
| Powertrain | ||
| Engine | 3.0L I6 diesel Turbo | 3.0L I6 diesel Turbo |
| Horsepower | 305 hp | 305 hp |
| Torque | 495 lb-ft | 495 lb-ft |
| Transmission | 10-speed shiftable automatic | 10-speed shiftable automatic |
| Drivetrain | 4WD | 4WD |
| Fuel Economy | ||
| City MPG | 22 | 22 |
| Highway MPG | 26 | 26 |
| Combined MPG | 24 | 24 |
| Fuel Tank | 24.0 gal | 24.0 gal |
| Dimensions | ||
| Curb Weight | 5,500 lbs | 5,500 lbs |
| Wheelbase | 148.0" | 148.0" |
| Length | 232.9" | 232.9" |
| Width | 81.2" | 81.2" |
| Height | 78.4" | 78.4" |
| Truck Specs | ||
| Cab Type | Crew Cab | Crew Cab |
| Bed Length | 5.8 ft | 5.8 ft |
| Safety | ||
| NHTSA Overall | 5/5 stars | 5/5 stars |
| Warranty | ||
| Bumper-to-Bumper | 3yr/36k | 3yr/36k |
| Powertrain | 5yr/60k | 5yr/60k |
| Corrosion | 6yr/100k | 6yr/100k |
| Roadside Assistance | 5yr/60k | 5yr/60k |
Frequently Asked Questions
What is the price difference between the 2025 GMC Sierra 1500 AT4 and 2026 GMC Sierra 1500 AT4?
The 2025 GMC Sierra 1500 AT4 starts at $66,800, $200 less than the 2026 GMC Sierra 1500 AT4 at $67,000. That gap is small enough that monthly payments are nearly identical. Focus on which vehicle fits your life, not the sticker.
Who should choose the 2025 GMC Sierra 1500 AT4?
The 2025 GMC Sierra 1500 AT4 is the stronger pick when you want to keep $200 in your pocket and the 2025 GMC Sierra 1500 AT4 covers your needs.
Who should choose the 2026 GMC Sierra 1500 AT4?
The 2026 GMC Sierra 1500 AT4 is the stronger pick when the 2026 GMC Sierra 1500 AT4 is more fuel-efficient for a lower-cost commute.
Which gets better fuel economy, the 2025 GMC Sierra 1500 AT4 or 2026 GMC Sierra 1500 AT4?
Both achieve 24 combined MPG, so fuel cost is not a factor in this decision.
Which is more powerful, the 2025 GMC Sierra 1500 AT4 or 2026 GMC Sierra 1500 AT4?
Both produce 305 hp.
Is the 2025 GMC Sierra 1500 AT4 bigger than the 2026 GMC Sierra 1500 AT4?
Both measure 232.9″ in overall length.
Explore more: GMC trims, GMC Sierra 1500 trims
How the Sierra 1500 and Sierra 1500 Stack Up
Two full-size trucks built for work and weekend. The 2025 GMC Sierra 1500 AT4 ($66,800) and 2026 GMC Sierra 1500 AT4 ($67,000) take different approaches to the same job. The $200 price gap works out to less than $10/month on a typical loan, so the cost difference is negligible. Pick on fit, not on price.
Powertrain: Sierra 1500 vs Sierra 1500
Both run the same 3.0L I6 diesel Turbo engine. Both produce 305 hp. Both use 4WD.
What It Actually Costs to Own
Annual fuel costs are nearly identical, so running costs will not separate these two.
Which One Should You Buy?
Choose the 2025 GMC Sierra 1500 AT4 when you want to keep $200 in your pocket and the 2025 GMC Sierra 1500 AT4 covers your needs. Choose the 2026 GMC Sierra 1500 AT4 when the 2026 GMC Sierra 1500 AT4 is more fuel-efficient for a lower-cost commute.
Specifications shown combine licensed third-party automotive data with official manufacturer, EPA, and NHTSA source material. Actual pricing, features, and availability may vary by region and dealer. Always confirm details with an authorized dealer before making a purchase decision. TrimAtlas is not affiliated with GMC or any dealership.