2012 GMC Sierra K15

Truck Flex Fuel
GMC Sierra K15 2012
17MPG Combined
5 Trims
← 2011 2012 2013 →
Updated February 27, 2026

The 2012 GMC Sierra K15 is a Truck that delivers 14–17 combined MPG depending on trim. Here’s everything you need to know about this vehicle, from fuel economy to safety ratings.

2012 GMC Sierra K15 Specifications

SpecValue
Combined MPG14–17 combined MPG depending on trim
City MPG15
Highway MPG21
Body StyleTruck
Fuel TypeFlex Fuel
Drive4WD
Available Trims5

Available Trims

TrimMPG (City/Hwy/Combined)EngineTransmission
Auto15/21/175.3L 8cylAutomatic 6-spd
Auto12/18/146.2L 8cylAutomatic 6-spd
Auto14/18/164.3L 6cylAutomatic 4-spd
Auto13/18/154.8L 8cylAutomatic 4-spd
Auto12/18/146.2L 8cylAutomatic 6-spd

Annual Fuel Cost

Based on EPA estimates, the 2012 GMC Sierra K15 costs approximately $2,920 per year in fuel. This assumes 15,000 miles driven annually and current fuel prices.

Compare the 2012 GMC Sierra K15

See how it stacks up against similar vehicles:

Other Model Years

Check Vehicle History

Considering a used GMC Sierra K15? Get a comprehensive vehicle history report including accident records, ownership history, and more.

🔍 Check GMC Sierra K15 Vehicle History Check VIN →
Check Vehicle History

Get the full story — accidents, ownership, recalls, odometer, and more. Decode any VIN instantly.

Check VIN
Buying a used GMC Sierra K15? Check VIN on RedVIN