FuelFacts

← all 2020 GMC Sierra 4WD AT4 trims

2020 GMC Sierra 4WD AT4 — 5.3L 8-cyl, Automatic 6-spd, 4WD

This 2020 GMC Sierra 4WD AT4 (5.3L 8-cyl, Automatic 6-spd, 4WD) takes regular (87-octane) gasoline. REGULAR

16
MPG combined (14 city / 18 hwy)
$3,562
est. fuel cost / year (today’s prices, 15k mi)
556 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 2020 GMC Sierra 4WD AT4 trims

TrimFuelMPGFuel/yr
5.3L 8-cyl, Automatic 8-spd, 4WDREGULAR18$3,167
5.3L 8-cyl, Automatic 10-spd, 4WDREGULAR18$3,167
3.0L 6-cyl, Automatic 10-spd, 4WDDIESEL24$2,988
6.2L 8-cyl, Automatic 10-spd, 4WDPREMIUM17$4,129

EPA fuel type: Regular · class: Standard Pickup Trucks 4WD · engine: 5.3L 8-cyl · transmission: Automatic 6-spd · drive: 4WD · MPG retrieved 2026-07-24.