2005-2011 Mercedes-Benz SLK-Class MPG & Fuel Cost

EPA rates the 2005-2011 Mercedes-Benz SLK-Class at 16–21 MPG combined across 32 configurations and 7 model years. The most efficient version, the 2011 SLK300 3.0L 6-cyl RWD, is rated 21 MPG (19 city, 26 highway).

The SLK300 3.0L 6-cyl RWD reached the generation's best combined rating, 21 MPG, in 2006, 2009, 2010 and 2011. The lowest top rating, 19 MPG, was in 2005.

Yes. Ratings changed in 2006, 2007, 2009, 2010 and 2011. In 2008 the values repeat the year before.

The previous generation (2004 Mercedes-Benz SLK-Class) is rated 17–22 MPG combined and costs $3,650–$4,730 a year to fuel; the 2005-2011 model is rated 16–21 MPG and costs $3,790–$5,020 a year.

Driving 15,000 miles a year at premium gasoline $5.36/gal (U.S. average, Sep 2026), the SLK300 3.0L 6-cyl RWD costs about $3,790 a year. Across all 4 configurations the cost runs $3,790–$3,940 a year. That is a $150 difference between the cheapest and the costliest configuration.

About $25.27 per 100 miles for the SLK300 3.0L 6-cyl RWD at premium gasoline $5.36/gal (U.S. average, Sep 2026), and between $25.27 and $26.27 across all configurations. That is the annual cost over 15,000 miles divided by 150.

The SLK300 3.0L 6-cyl RWD is rated 19 city and 26 highway MPG, so it is more efficient on the highway, by 7 MPG.

The SLK300 3.0L 6-cyl RWD costs about $3,790 a year to fuel, $150 less than the class median of $3,940, and less than 6 of 10 two-seater configurations. The comparison covers all 67 rated two-seater configurations for MY2011, not weighted by sales.

The most efficient configuration stays at 21 MPG. Its annual cost goes from $3,830 to $3,790, $40 less. EPA lists 4 configurations for 2011 against 5 configurations for 2010. See the 2010 Mercedes-Benz SLK-Class for that year.