The Mercedes-Benz GL550 4MATIC was a variant of the X166 GL-Class that debuted for the 2013 model year replacing the X164 GL550. The GL 550 4MATIC was powered by Mercedes' M278 DE46 engine, which was a 429hp twin-turbo 4.7L V8 paired to a 7-speed 7G-Tronic automatic transmission that sent power to all four wheels. Production of the X166 Mercedes-Benz GL550 4MATIC lasted until 2015, when Mercedes changed the name of the GL to GLS, and the GL550 became the GLS550 4MATIC starting for the 2016 model year.