The 2020 Mercedes-Benz GLS-Class overperforms in any configuration. We’re just fine with the base 2020 GLS 450, which easily earns a 7 out of 10 score for its comfortable ride and its strong, smooth powertrain.
Underhood, the GLS 450 makes use of a 362-horsepower, 369 pound-feet of torque 3.0-liter turbo-6 paired with a 48-volt electric starter generator and battery that can provide an additional 21 hp and 184 lb-ft of torque. The 48-volt system takes away any hint of turbo lag and helps the powertrain compensate for electrical draw from accessories such as the air conditioning system.
The standard engine is so strong, so silent, and so refined that it’s hard to imagine opting for the GLS 580 with its 483-hp, 516 lb-ft of torque 4.0-liter turbocharged V-8. The GLS 580 also benefits from the 48-volt integrated starter generator system’s power boost and it uses a version of the 9-speed automatic transmission found in the GLS 450.
Short of providing more power to handle trailers as heavy as 7,650 pounds, the big engine is overkill for most users. In our initial preview drive, we found transmission tuning in the GLS 580 to downshift too eagerly, vaulting the massive SUV to illegal speeds in a blink.
2020 Mercedes-Benz GLS-Class ride and handling
Underneath, the GLS comes standard with an air suspension that can be softened or firmed up at the tap of a drive mode button. The softest mode floats over bumps with land yacht-like comfort, while Sport and Sport+ modes tighten reflexes for more control. We found Sport to be the Golidlocks of suspension modes, and Mercedes conveniently includes an Individual setting that allowed us to keep the Sport suspension setting with the Comfort drivetrain setup.
Optional on both engines is the E-Active Body Control system that uses the 48-volt integrated starter motor to control each wheel’s spring forces individually. Using the adaptive cruise control’s myriad sensors that watch the road ahead, E-Active Body Control prepares each wheel for pavement imperfections. The system works fabulously to tame bumpy roads, but we found it to result in unnatural-feeling motions on winding pavement as it attempted to keep the SUV’s passenger compartment level. Try both, but we’re not sure we’d spend for E-Active Body Control given how well the GLS rides on its stock air suspension.
The GLS has a nimble feel in urban situations and it settles comfortably into high-speed highway cruising. Its steering delivers little communication to the driver, but that’s not really the point of a hulking SUV.
An optional off-road package includes a special four-wheeling traction control mode, though it’s hard to imagine many buyers will choose the GLS for its adventuring abilities.
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