2021 Mercedes-AMG GLS 63 SUV is 603hp seating for seven

Just how fast do you need you uber-luxury SUV to actually go? If you're Mercedes-Benz, and the glitzy truck in question is the 2021 Mercedes-AMG GLS 63, the answer is apparently 0-60 mph in 4.1 seconds and an electronically-limited top speed of 174 mph. Not bad at all for something with seating for up to seven.

It's the latest example of what the automaker is calling "the S Class of SUVs," and power isn't in short supply. The AMG 4.0-liter V8 biturbo engine is good for 603 horsepower and 627 lb-ft of torque, but EQ Boost can contribute up to 21 hp and 184 lb-ft more when required.

That's all funneled via a 9-speed transmission to AMG's Performance 4MATIC+ all-wheel drive. The front and rear axles are permanently linked, with the torque distribution capable of pushing all of the power to the rear if required, or up to 50-percent to the front. How that is decided depends, in part, on which AMG Dynamic Select mode you're in, from Comfort and Sport, through Sport+, Individual, Trail, and Sand.

Air suspension with adjustable damping is standard, again with three modes to choose between – Comfort, Sport, and Sport+ – along with AMG Active Ride Control with a 48v active roll stabilization system. That uses two independent electro-mechanical actuators, one for each axle, to stiffen the SUV up as required such as when you're cornering.

The 48v electrical system is also used for EQ Boost. That uses an electric starter generator to contribute extra horsepower and torque for a short period of time, its battery charged up while you're driving through regenerative braking.

Inside, there's the option of seven seats or six captain's chairs. As you'd expect from the SUV's positioning, the AMG GLS 63 is a pretty luxurious place: there's leather all around, 64-color ambient lighting, AMG front seats with heating and massage, and heated second-row seats. Mercedes' MBUX infotainment system with voice control is standard, as is a 12.3-inch digital cluster display and a matching 12.3-inch touchscreen.

360-degree view, parking assistance, adaptive cruise control, Android Auto, Apple CarPlay, and a Burmester Surround Sound system are standard. There's also heated and cooled front cupholders, and the option of an Executive Rear Seat Package with a foldable center console with its own 7-inch MBUX tablet. That extends the front wireless phone charging to a pad in the second row, too.

The whole thing rides on 21-inch AMG wheels as standard – up to 23-inches are available – with a striking body kit and dynamic LED headlamps. Pricing in the US isn't confirmed yet, but Mercedes says to expect the 2021 AMG GLS 63 SUV by mid-2020.