The Cadillac STS (for Seville Touring Sedan), previously called Seville, is a luxury mid-size sedan which competes with heavyweights such as the Audi A6, BMW 5 Series, Mercedes E-Class and Lexus GS.  When the Seville becomes the STS (2005 model car), it goes from front-wheel drive to rear-wheel drive (all-wheel drive remains an option) and its design becomes drastically younger.  In 2006, General Motors introduced the STS-V.  This new version, more powerful and sporty, is then powered by a supercharged Northstar 4.4 liter V8 producing 469 horsepower.