The Mercedes-Benz GL63 AMG was a high-performance variant of the X166 GL-Class that debuted for the 2014 model year. The GL 63 AMG was powered by Mercedes' M157 DE55 engine, which was a 550hp twin-turbo 5.5L V8 paired to a 7-speed 7G-Tronic automatic transmission that sent power to all four wheels. In addition to the powerful engine, these SUVs also received upgraded suspension, brakes, and exhaust. The X166 Mercedes-Benz GL63 AMG, which was built until 2015, was facelifted and renamed as the GLS63 AMG for the 2016 model year.