AMG's two newest high-performance SUVs both wear the 63 suffix, and that's not a coincidence; they're powered by the same engine. While the nameplate no longer denotes a 6.3-liter engine, it signals the presence of a twin-turbocharged, 4.0-liter V8 rated at 603 horsepower and 627 pound-feet of torque. There's also a 48-volt starter-generator that adds 21 horses and 184 pound-feet of twist in short bursts. 4Matic all-wheel drive and a nine-speed automatic transmission come standard.
The GLE takes 3.7 seconds to reach 60 mph from a stop, a figure that makes it nearly half a second quicker than its bigger sibling, and puts it in the same ballpark as many smaller, lighter sports cars. AMG promised the 48-volt mild hybrid system and its cylinder shut-off technology make the GLE more efficient than its impressive performance specifications suggest.
An adaptive air suspension filters out road imperfections before they reach the occupants' spines. The system automatically lowers the ride height by 0.4 inches when the GLE goes above 75 mph, or when the driver selects one of the three AMG-designed driving modes. This yields a small improvement in fuel economy by reducing drag, and it improves handling by lowering the center of gravity. Alternatively, two driving modes named Trail and Sand, respectively, raise the suspension by about two inches to ensure rocks and ruts don't have a costly encounter with the V8's oil pan.
The 48-volt system also powers AMG's Active Ride Control technology, which keeps body lean in check, and maintains the body level when driving on an uneven road. Speed-sensitive power steering and bigger brakes on both axles (including 16-inch front rotors) are also part of the package. All told, the GLE and the GLS share much more than a nameplate.
The exterior updates are reasonably subtle, which is par for the course for Mercedes-Benz's go-fast division. The 63 S stands out from the regular GLE with a full body kit that adds AMG's Panamericana grille, new-look lower bumpers on both sides, side skirts, and 21-inch alloy wheels. Inside, the AMG treatment brings sport seats for the front passengers, plus model-specific graphics for the digital instrument cluster and the touchscreen-based MBUX infotainment system.
The 2021 Mercedes-AMG GLE 63 S will begin arriving in American showrooms in the middle of 2020. Pricing information and fuel economy figures won't be released until closer to its on-sale date.