The Mercedes-Benz SLK350 was a variant of the R171 SLK-Class that was introduced for the 2005 model year. The SLK 350 was powered by Mercedes' M272 E35 engine, which was a 3.5L V6 that originally generated 268hp. From the 2009 model year, this M272 engine was given various improvements which increased power to 301hp. These rear wheel drive sports cars were available with manual and automatic transmissions. Production of the R171 SLK350 ended in 2011, but the model series continued life in the next generation of SLK as the R172 Mercedes-Benz SLK350 BlueEFFICIENCY.