Does the 2026 GMC Sierra 4WD AT4X need premium gas?
Fuel grade varies by trim — see the breakdown below.
| Trim (engine / transmission) | Fuel | MPG | Fuel/yr |
|---|---|---|---|
| 3.0L 6-cyl, Automatic 10-spd, 4WD | DIESEL | 19 | $4,100 |
| 6.2L 8-cyl, Automatic 10-spd, 4WD | PREMIUM | 15 | $5,150 |
The EPA records the fuel each version was tested on. Whether premium is strictly required or just recommended is an owner's-manual detail the EPA dataset doesn't include — so we don't guess it.
2 trim(s) · EPA FuelEconomy.gov · retrieved 2026-06-14.