Cadillac STS MPG by Year & Engine (EPA)

EPA fuel-economy ratings for every rated Cadillac STS model year from 2005 to 2011 — each engine and transmission with its official city, highway and combined figures. Over these years the STS has been offered with 3.6L 6-cyl, 4.6L 8-cyl, 4.4L 8-cyl engines; the most efficient version is the 2011 (up to 21 MPG combined). Data: U.S. Department of Energy & EPA, fueleconomy.gov; prices are live medians from VehiSales listings.

Cadillac STS fuel economy by year

YearCombinedEnginesMedian used priceFor sale
2011 21 MPG 3.6L 6-cyl
2010 17–21 MPG 3.6L 6-cyl, 4.6L 8-cyl
2009 15–20 MPG 3.6L 6-cyl, 4.6L 8-cyl, 4.4L 8-cyl
2008 15–20 MPG 3.6L 6-cyl, 4.6L 8-cyl, 4.4L 8-cyl
2007 15–19 MPG 3.6L 6-cyl, 4.6L 8-cyl, 4.4L 8-cyl
2006 14–19 MPG 3.6L 6-cyl, 4.6L 8-cyl, 4.4L 8-cyl
2005 17–18 MPG 4.6L 8-cyl, 3.6L 6-cyl

2011 Cadillac STS: engines & MPG

The 2011 STS was EPA-rated in 2 versions (3.6L 6-cyl), with combined economy of 21 MPG.

VersionEngineTransmissionFuelCityHwyCombined
STS AWD 3.6L 6-cyl Automatic (S6) Regular 18 26 21 MPG
STS 3.6L 6-cyl Automatic (S6) Regular 18 27 21 MPG

2010 Cadillac STS: engines & MPG

The 2010 STS was EPA-rated in 4 versions (3.6L 6-cyl, 4.6L 8-cyl), with combined economy from 17 to 21 MPG.

VersionEngineTransmissionFuelCityHwyCombined
STS AWD 3.6L 6-cyl Automatic (S6) Regular 18 27 21 MPG
STS 3.6L 6-cyl Automatic (S6) Regular 18 27 21 MPG
STS 4.6L 8-cyl Automatic (S6) Regular 15 24 18 MPG
STS AWD 4.6L 8-cyl Automatic (S6) Regular 15 22 17 MPG

2009 Cadillac STS: engines & MPG

The 2009 STS was EPA-rated in 5 versions (3.6L 6-cyl, 4.6L 8-cyl, 4.4L 8-cyl), with combined economy from 15 to 20 MPG.

VersionEngineTransmissionFuelCityHwyCombined
STS AWD 3.6L 6-cyl Automatic (S6) Regular 17 26 20 MPG
STS 3.6L 6-cyl Automatic (S6) Regular 17 26 20 MPG
STS 4.6L 8-cyl Automatic (S6) Premium 15 24 18 MPG
STS AWD 4.6L 8-cyl Automatic (S6) Premium 15 22 17 MPG
STS-V 4.4L 8-cyl Automatic (S6) Premium 13 19 15 MPG

2008 Cadillac STS: engines & MPG

The 2008 STS was EPA-rated in 5 versions (3.6L 6-cyl, 4.6L 8-cyl, 4.4L 8-cyl), with combined economy from 15 to 20 MPG.

VersionEngineTransmissionFuelCityHwyCombined
STS AWD 3.6L 6-cyl Automatic (S6) Regular 17 26 20 MPG
STS 3.6L 6-cyl Automatic (S6) Regular 17 26 20 MPG
STS 4.6L 8-cyl Automatic (S6) Premium 15 24 18 MPG
STS AWD 4.6L 8-cyl Automatic (S6) Premium 14 21 16 MPG
STS-V 4.4L 8-cyl Automatic (S6) Premium 13 19 15 MPG

2007 Cadillac STS: engines & MPG

The 2007 STS was EPA-rated in 5 versions (3.6L 6-cyl, 4.6L 8-cyl, 4.4L 8-cyl), with combined economy from 15 to 19 MPG.

VersionEngineTransmissionFuelCityHwyCombined
STS 3.6L 6-cyl Automatic (S5) Regular 16 25 19 MPG
STS AWD 3.6L 6-cyl Automatic (S5) Regular 16 23 18 MPG
STS 4.6L 8-cyl Automatic (S6) Premium 15 24 18 MPG
STS 4.6L 8-cyl Automatic (S6) Premium 14 21 16 MPG
STS-V 4.4L 8-cyl Automatic (S6) Premium 12 19 15 MPG

2006 Cadillac STS: engines & MPG

The 2006 STS was EPA-rated in 5 versions (3.6L 6-cyl, 4.6L 8-cyl, 4.4L 8-cyl), with combined economy from 14 to 19 MPG.

VersionEngineTransmissionFuelCityHwyCombined
STS 3.6L 6-cyl Automatic (S5) Regular 16 25 19 MPG
STS 4.6L 8-cyl Automatic (S5) Premium 15 24 18 MPG
STS AWD 3.6L 6-cyl Automatic (S5) Regular 15 23 18 MPG
STS AWD 4.6L 8-cyl Automatic (S5) Premium 14 21 17 MPG
STS-V 4.4L 8-cyl Automatic (S6) Premium 12 19 14 MPG

2005 Cadillac STS: engines & MPG

The 2005 STS was EPA-rated in 3 versions (4.6L 8-cyl, 3.6L 6-cyl), with combined economy from 17 to 18 MPG.

VersionEngineTransmissionFuelCityHwyCombined
STS 2WD 4.6L 8-cyl Automatic (S5) Premium 15 23 18 MPG
STS 2WD 3.6L 6-cyl Automatic (S5) Regular 16 23 18 MPG
STS AWD 4.6L 8-cyl Automatic (S5) Premium 14 21 17 MPG

Frequently asked questions

What MPG does a Cadillac STS get?

Depending on year and engine, EPA combined ratings for the STS range from 18 to 21 MPG. The most efficient rated version is the 2011 model year.

What engines does the 2011 Cadillac STS have?

The 2011 STS was EPA-rated with 3.6L 6-cyl engines — see the 2011 table above for each version's exact city/highway figures.

Does the Cadillac STS require premium gas?

Some versions do: EPA lists regular gasoline and premium gasoline depending on year and engine — check your year's table above.

About this data: EPA ratings from the official U.S. DOE/EPA dataset (fueleconomy.gov), as of July 2026; refreshed monthly. Market prices and listing counts are live medians from VehiSales inventory, updated daily. How to cite: “VehiSales Research, Cadillac STS EPA Fuel Economy by Model Year” with a link to https://vehisales.com/research/fuel-economy/cadillac/sts.

See also: Cadillac STS hub — live listings, prices & reliability · Most fuel-efficient cars by segment · Model price trends. Media inquiries: [email protected].

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