2026 head-to-head · Full-Size Pickup
2026 Chevrolet Colorado vs GMC Sierra Diesel
MPG, range and what each one really costs you to fuel, from official EPA ratings and recalculated with your own gas and electricity prices.
On fuel costs these two are nearly tied. Driving 15,000 miles a year with $3.10/gal regular gas and $3.70/gal diesel fuel, the most efficient 2026 Chevrolet Colorado (21 MPG) costs about $2,214 a year to fuel and the 2026 GMC Sierra Diesel (25 MPG) about $2,220.
Your numbers
Change these to match your driving and local prices. Every figure and chart on this page updates.
Fuel cost over 10 years
- Chevrolet Colorado
- GMC Sierra Diesel
Side by side
| Chevrolet Colorado | GMC Sierra Diesel | |
|---|---|---|
| $2,214 | Your annual fuel cost | $2,220 |
| 21 MPG | Combined efficiency | 25 MPG |
| 19 MPG | City | 23 MPG |
| 24 MPG | Highway | 28 MPG |
| 420 g/mi | Tailpipe CO₂ (g/mi) | 402 g/mi |
| 4/10 | EPA fuel economy score | 5/10 |
| 4/10 | EPA greenhouse gas score | 4/10 |
| Gas | Powertrain | Diesel |
| Regular gasoline | Fuel | Diesel |
| 2.7L 4-cyl turbo | Engine / motor | 3.0L 6-cyl turbo |
| 8-speed automatic | Transmission | 10-speed automatic |
| RWD | Drivetrain | RWD |
✓ marks the better value. EPA scores run 1–10 (10 is best). Volumes come from the EPA interior volume index and aren't published for every body style.
Chevrolet Colorado vs GMC Sierra Diesel across model years
- Chevrolet Colorado
- GMC Sierra Diesel
Annual fuel cost of the most efficient configuration of each model year, at your prices. Click a point to open that year.
How they differ
Among 21 2026 full-size pickups, the Chevrolet Colorado ranks 12th and the GMC Sierra Diesel 15th for lowest fuel cost.
The powertrains differ: the Chevrolet Colorado is a conventional gas model, while the GMC Sierra Diesel is a diesel.
Frequently asked questions
Which is more fuel-efficient, the 2026 Chevrolet Colorado or the 2026 GMC Sierra Diesel?
Measured by cost to drive, the Chevrolet Colorado. The Chevrolet Colorado is rated 21 MPG combined and the GMC Sierra Diesel 25 MPG (EPA, most efficient configuration of each).
How much does it cost to fuel the 2026 Chevrolet Colorado vs. the GMC Sierra Diesel per year?
At 15,000 miles a year with $3.10/gal regular gas and $3.70/gal diesel fuel, about $2,214 for the Chevrolet Colorado and $2,220 for the GMC Sierra Diesel.
Chevrolet Colorado vs GMC Sierra Diesel in other years
More 2026 comparisons
Chevrolet Colorado vs…
Or compare the 2026 Chevrolet Colorado with anything else: