← all 2021 GMC Sierra 2WD trims
2021 GMC Sierra 2WD — 2.7L 4-cyl, Automatic 8-spd, RWD
This 2021 GMC Sierra 2WD (2.7L 4-cyl, Automatic 8-spd, RWD) takes regular (87-octane) gasoline. REGULAR
21
MPG combined (20 city / 23 hwy)
$2,714
est. fuel cost / year (today’s prices, 15k mi)
421 g/mi
tailpipe CO₂
At today's AAA national average price ($3.80/gal, 2026-07-05) — the EPA's own price/date assumption isn't exposed in the public dataset, so we recompute this from the EPA's MPG figure and a sourced current price.
Other 2021 GMC Sierra 2WD trims
| Trim | Fuel | MPG | Fuel/yr |
|---|---|---|---|
| 2.7L 4-cyl, Automatic 8-spd, RWD | REGULAR | 21 | $2,714 |
| 5.3L 8-cyl, Automatic 8-spd, RWD | REGULAR | 19 | $3,000 |
| 5.3L 8-cyl, Automatic 6-spd, RWD | REGULAR | 17 | $3,353 |
| 4.3L 6-cyl, Automatic 6-spd, RWD | REGULAR | 17 | $3,353 |
| 5.3L 8-cyl, Automatic 8-spd, RWD | REGULAR | 17 | $3,353 |
| 5.3L 8-cyl, Automatic 6-spd, RWD | REGULAR | 16 | $3,562 |
| 3.0L 6-cyl, Automatic 10-spd, RWD | DIESEL | 26 | $2,758 |
| 5.3L 8-cyl, Automatic 6-spd, RWD | FLEX-FUEL | 16 | $3,900 |
EPA fuel type: Regular · class: Standard Pickup Trucks 2WD · engine: 2.7L 4-cyl turbo · transmission: Automatic 8-spd · drive: RWD · MPG retrieved 2026-07-24.