2021 head-to-head · Full-Size Pickup
2021 GMC Sierra vs Ram 1500 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.
The 2021 Ram 1500 Diesel is the cheaper one to run. Driving 15,000 miles a year with $3.10/gal regular gas and $3.70/gal diesel fuel, it costs about $2,135 a year to fuel (26 MPG), versus $2,214 for the 2021 GMC Sierra (21 MPG). That's roughly $80 a year, or about $398 over five years.
Your numbers
Change these to match your driving and local prices. Every figure and chart on this page updates.
Fuel cost over 10 years
- GMC Sierra
- Ram 1500 Diesel
Side by side
| GMC Sierra | Ram 1500 Diesel | |
|---|---|---|
| $2,214 | Your annual fuel cost | $2,135 |
| 21 MPG | Combined efficiency | 26 MPG |
| 20 MPG | City | 22 MPG |
| 23 MPG | Highway | 32 MPG |
| 421 g/mi | Tailpipe CO₂ (g/mi) | 390 g/mi |
| 4/10 | EPA fuel economy score | 5/10 |
| 4/10 | EPA greenhouse gas score | 5/10 |
| Gas | Powertrain | Diesel |
| Regular gasoline | Fuel | Diesel |
| 2.7L 4-cyl turbo | Engine / motor | 3.0L 6-cyl turbo |
| 8-speed automatic | Transmission | 8-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.
GMC Sierra vs Ram 1500 Diesel across model years
- GMC Sierra
- Ram 1500 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 17 2021 full-size pickups, the GMC Sierra ranks 8th and the Ram 1500 Diesel 7th for lowest fuel cost.
The powertrains differ: the GMC Sierra is a conventional gas model, while the Ram 1500 Diesel is a diesel.
Frequently asked questions
Which is more fuel-efficient, the 2021 GMC Sierra or the 2021 Ram 1500 Diesel?
Measured by cost to drive, the Ram 1500 Diesel. The GMC Sierra is rated 21 MPG combined and the Ram 1500 Diesel 26 MPG (EPA, most efficient configuration of each).
How much does it cost to fuel the 2021 GMC Sierra vs. the Ram 1500 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 GMC Sierra and $2,135 for the Ram 1500 Diesel.
GMC Sierra vs Ram 1500 Diesel in other years
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