The Cadillac STS (Seville Touring Sedan) is a mid-sized luxury 4-door sedan manufactured and marketed by General Motors from 2004 to 2011 for the 2005 to 2011 model years. A version of the STS was sold in China as the SLS through 2013. It was equipped with a six-speed automatic transmission with performance algorithm shifting and driver shift control. The STS was the successor to the Cadillac Seville, which beginning in 1987 was available as an upscale performance-oriented STS (for Seville Touring Sedan) version. While smaller than the full-size DTS, the more expensive STS was the flagship sedan of the Cadillac brand. (Source: Wikipedia.org, CC BY-SA)