The Mercedes-Benz GLS63 AMG 4MATIC was a all-wheel drive, performance-focused variant of the X166 GL-Class that debuted for the 2016 model year after a facelift and renaming of all GL-Class variants to GLS-Class. The GLS 63 AMG 4MATIC was powered by Mercedes' M157 DE55 engine, which was a 577hp 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 more powerful engine, the GLS63 featured upgraded suspension, brakes, and exhaust. The X166 Mercedes-Benz GLS 63 AMG 4MATIC was built until 2019, and was replaced by the X167 GLS63 AMG 4MATIC+ for the 2020 model year.