Does the 2015 GMC Sierra K15 4WD take premium or regular gas?

The EPA lists the 2015 GMC Sierra K15 4WD 5.3L 8-cyl, Automatic 6-spd, 4WD as taking flex-fuel. Combined MPG is 18, and at today's gas prices that's about $3,450 a year in fuel.

← all 2015 GMC Sierra K15 4WD trims

2015 GMC Sierra K15 4WD — 5.3L 8-cyl, Automatic 6-spd, 4WD

This 2015 GMC Sierra K15 4WD (5.3L 8-cyl, Automatic 6-spd, 4WD) is flex-fuel (gasoline or E85). FLEX-FUEL

MPG combined (16 city / 22 hwy)

$3,450

est. fuel cost / year (EPA, 15k mi)

490 g/mi

tailpipe CO₂

EPA updated its fuel-economy equations again for model year 2017 — mostly affecting hybrids and turbocharged engines — and recalculated 2011-2016 ratings to match, in some cases 1-2 MPG lower. The number above already reflects that update.

Other 2015 GMC Sierra K15 4WD trims

Trim	Fuel	MPG	Fuel/yr
5.3L 8-cyl, Automatic 6-spd, 4WD	REGULAR	18	$3,167
6.2L 8-cyl, Automatic 8-spd, 4WD	REGULAR	17	$3,353
4.3L 6-cyl, Automatic 6-spd, 4WD	FLEX-FUEL	19	$3,300

EPA fuel type: Gasoline or E85 · class: Standard Pickup Trucks 4WD · engine: 5.3L 8-cyl · transmission: Automatic 6-spd · drive: 4WD · MPG retrieved 2026-07-24.