The Mercedes-Benz GLS63 AMG (X166, 2016–2019) is a full-size performance SUV powered by AMG's 5.5L twin-turbocharged M157 V8, producing 577 hp and 561 lb-ft of torque. It sends power through a 7-speed AMG SPEEDSHIFT automatic transmission and 4MATIC all-wheel drive, while AMG performance hardware includes an AIRMATIC air suspension, adaptive damping, performance exhaust, larger brakes, and an AMG-tuned transfer case.

The GLS63 AMG is notable for combining three-row luxury, full-size dimensions, and genuine AMG performance hardware in a package capable of supercar-like acceleration. Its twin-turbo V8, adaptive air suspension, and electronically controlled AWD make the X166 a landmark in the evolution of the high-performance full-size SUV, establishing the formula later refined by the more powerful GLS63 generations.