2021 Mercedes-Benz GLS Review

Christian Wardlaw, Independent Expert | Nov 24, 2021

Introduction - Find the best Mercedes-Benz deals!

Full-size luxury SUV shoppers may forget that Mercedes-Benz offers an alternative to the Cadillac EscaladeGMC Yukon Denali, and Lincoln Navigator. Better yet, the 2021 Mercedes-Benz GLS is built right here in the U.S. of A., at a factory in Alabama. And it carries a competitive starting price.

When Mercedes redesigned the GLS for 2020, the SUV arrived in GLS 450 and GLS 580 specification. For 2021, two new versions of the GLS are available. The first is the AMG GLS 63, a performance-tuned variant. The second is the Maybach GLS, a super-luxury model starting at more than twice the price of a GLS 450.

Aside from the two new specialty models, the current-generation GLS enters its sophomore year with newly standard 20-inch alloy wheels, a 4-zone automatic climate control system, ventilated front seats, and an enhanced alarm system that detects parking damage. New upholstery choices are also available.

What Owners Say About the Mercedes-Benz GLS - Find the best Mercedes-Benz deals!

2021 Mercedes-AMG GLS 63 White Front Quarter View

Photo: Christian Wardlaw

The Mercedes-Benz GLS competes in the Large Premium SUV market segment. According to data collected from verified new-vehicle buyers for the J.D. Power 2021 Automotive Performance, Execution and Layout (APEAL) Study, 73 percent of new Mercedes GLS buyers are male (vs. 68 percent for the segment), and the median age of a GLS buyer is 58 years (vs. 55).

As part of the APEAL Study, owners rated the Mercedes GLS in 10 primary categories. Listed below in descending order, you’ll find their preferences from their most favorite thing about the vehicle to their least favorite:

  • Driving feel
  • Powertrain
  • Feeling of safety
  • Interior design
  • Exterior styling
  • Driving comfort
  • Infotainment
  • Getting in and out
  • Setting up and starting
  • Fuel economy

In the 2021 APEAL Study, the GLS ranks fourth out of seven Large Premium SUV models.

What Our Independent Expert Says About the Mercedes-Benz GLS - Find the best Mercedes-Benz deals!

In the sections that follow, our independent expert provides an analysis of a 2021 Mercedes-AMG GLS 63 equipped with the following options:

  • Extra-cost paint
  • Carbon fiber engine compartment cover
  • AMG Night package
  • AMG 23-inch forged aluminum wheels
  • AMG Exclusive leather seats
  • AMG carbon fiber interior trim
  • AMG performance steering wheel with carbon fiber and Dinamica suede trim
  • Exclusive Trim package
  • Acoustic Comfort package
  • MBUX Technology package
  • MBUX Interior Assistant
  • Warmth and Comfort package
  • Energizing Comfort package Plus
  • Magic Vision Control wiper system
  • Rear side airbags

The price of the test vehicle came to $150,445, including the $1,050 destination charge.

Getting In and Getting Comfortable

2021 Mercedes-AMG GLS 63 Front Seats

Photo: Christian Wardlaw

Unless you kneel the air suspension, the GLS requires a bit of a step up in order to enter the SUV. Also, the rear doors are long and open wide, making them a hassle in cramped parking situations.

Once you and your passengers have climbed aboard, you’ll revel in high-end design, intricate detailing, and, for the most part, impeccable materials. Mercedes uses hard plastic rather than padded surfaces on the lower door panels, which might be appropriate in the GLS 450 but certainly attract a critical eye in an AMG GLS 63 wearing a $150K price tag.

The controls are typical of a modern Mercedes-Benz. Because the test vehicle featured AMG specification, the emphasis was on quick access to performance attributes such as suspension and exhaust settings instead of commonly desired features such as the heating, ventilation, and massage functions for the seats.

Up front, the leather-swaddled chairs offer plenty of long-distance comfort. The second-row seats are also satisfying, and the standard 4-zone automatic climate control system ensures greater family harmony. But I was surprised to discover that the test vehicle had no rear side window sunshades.

A GLS can carry six adults in relative comfort. The key is to have the people in the second-row seats move forward a little and bring their seatbacks into a more upright position. Accessing the third-row seat is a graceless exercise, and it takes an interminably long time for the second-row seat to power itself forward to add clearance. Better hope it’s not raining outside.

2021 Mercedes GLS MBUX Infotainment System Review

2021 Mercedes-AMG GLS 63 Interior Dashboard

Photo: Christian Wardlaw

Every 2021 Mercedes GLS includes a Mercedes-Benz User Experience (MBUX) infotainment system with dual 12.3-inch digital displays. One resides in front of the driver and serves as the instrumentation. The other lives to the right of it and has a touchscreen display. You can use the screen, the center console controls, the steering wheel controls, or the digital voice assistant to operate the various MBUX functions.

Highlights of MBUX include:

  • 12.3-inch digital instrumentation display
  • 12.3-inch touchscreen infotainment system display
  • Natural-voice recognition
  • “Hey Mercedes” digital assistant
  • Touchpad center console controller
  • Touch-sensing buttons on the steering wheel
  • Bluetooth
  • Apple CarPlay
  • Android Auto
  • Satellite radio
  • Navigation system
  • Wireless smartphone charging
  • Mercedes Me connected services
  • In-car Communication System (via stereo speakers)
  • Burmester surround-sound premium audio system

Optional upgrades to MBUX include:

  • MBUX Interior Assistant (gesture control)
  • Augmented video for the navigation system
  • Wi-Fi service
  • Head-up display
  • High-end Burmester audio components

Setting up the technology takes some time, but if you’re familiar with a smartphone or tablet computer, you’ll understand what is necessary to find, select, and change settings to your personal preferences.

Overall, MBUX is one of the better infotainment systems available in a modern automobile. The full-color, high-definition screens look great night or day, the voice-recognition system works beautifully, and the Burmester audio system supplies rich sound.

However, a full day spent on a family excursion to new places in Los Angeles revealed the following wish list:

  • Easier access to the head-up display adjustments
  • A physical control for tuning the radio, similar to what Mercedes provides for volume
  • Wireless smartphone mirroring to eliminate cables

Otherwise, despite its inherent complexity, MBUX is fairly easy to use if not flawless. It responds to input quickly and returns mostly accurate results, and the augmented video for navigation feature is especially handy in dense urban areas and after nightfall.

What It’s Like to Drive the 2021 Mercedes-Benz GLS

2021 Mercedes-AMG GLS 63 White Side View

Photo: Christian Wardlaw

Mercedes equips the GLS 450 with a turbocharged 3.0-liter inline 6-cylinder engine and standard 4Matic variable all-wheel-drive system. It makes 362 horsepower and 369 pound-feet of torque and accelerates to 60 mph in a claimed 5.9 seconds.

Other GLS models use a twin-turbocharged 4.0-liter V8 tuned to deliver between 483 and 603 hp and between 516 and 627 pound-feet of torque, depending on the version of the SUV. According to Mercedes, acceleration to 60 mph takes anywhere between 4.1 and 5.2 seconds.

All 2021 GLS engines employ the automaker’s EQ Boost 48-volt mild-hybrid technology and an Integrated Starter-Generator (ISG) to maximize power and efficiency simultaneously. Official fuel-economy ratings range from 16 mpg to 21 mpg in combined driving, depending on the model. The GLS can tow up to 7,700 pounds when properly equipped.

Via Dynamic Select, drivers can alter the SUV’s driving character. An Airmatic air suspension is standard, with adaptive damping. An E-Active Body Control system is available with the V8 engine, designed to eliminate body lean, tilt, pitch, and dive to create a smoother ride for passengers.

Naturally, the AMG GLS 63 gets the complete AMG engineering treatment, with modifications to the powertrain, suspension, brakes, and exhaust. The test vehicle also had 23-inch AMG-designed Monoblock forged-aluminum wheels that miraculously did not utterly destroy the GLS’s ride quality.

Equipped with the most potent version of the twin-turbo V8, the AMG GLS 63 delivers stunning acceleration, and it sounds magnificent when your foot is heavy on the go pedal. It’s really hard to wrap your head around how a vehicle of this size and weight can get to freeway speeds so fast, but as the auto industry transitions to electric powertrains, such vehicle behavior will become the norm.

The AMG Speedshift 9-speed automatic transmission is flawless; smooth, fast, and barely noticeable unless you’re in Sport+ mode. And in that instance, its behavior perfectly matches driver expectations.

Sport+ mode also activates a transmission downshift rev-matching feature, makes the exhaust system louder, and adjusts the suspension so that it masterfully manages the SUV’s considerable weight. Additionally, the massive 23-inch wheels and tires supply superhuman grip in curves and corners. Taken together, when you’re really hustling this linebacker of an SUV in Sport+ mode, it proves unexpectedly good to drive.

In typical driving situations, though, you’ll likely prefer the Comfort driving mode. This more relaxed dynamic state does allow more body motion than you might expect, given the standard AMG Active Ride Control suspension with roll stabilization. Fortunately, the AMG Dynamic Select technology has an Individual setting, allowing owners to firm up the suspension while retaining a quieter and more efficient drivetrain behavior.

There isn’t much you can do about the brake pedal, though. It operates an impressive set of 15.7-inch perforated front and 14.6-inch rear disc brakes, complete with 6-piston front calipers. At speed, the brakes are brilliant. When mired in L.A. traffic, the pedal feels inconsistent in terms of feel and response, and it can be challenging to bring the AMG GLS 63 to a smooth, clean stop.

Also, you’ll want to think twice about the 23-inch wheels. They look cool, but the cost of replacement tires could give you a heart attack, and I did experience an unusual amount of tramlining on the freeways in my region of the country.

Overall, though the AMG GLS 63 is an impressive piece of work, I think most people would be happier driving the GLS 450 or the GLS 580 every day.

Driver Assistance Package Plus Review

2021 Mercedes-AMG GLS 63 Driving Assistance Systems

Photo: Christian Wardlaw

The list of standard and available advanced driving assistance systems (ADAS) for the 2021 Mercedes GLS is extensive, containing almost 20 features that aid a driver and can actively attempt to avoid a collision. The AMG GLS 63 includes them all.

These are the uncommon features among them:

  • Crosswind Assist (helps to stabilize the SUV in stiff crosswinds)
  • Evasive Steering Assist (helps to stabilize the SUV when the driver takes evasive action to avoid an obstacle)
  • Active Emergency Stop Assist (brings the SUV to a safe stop if a driver becomes unresponsive)
  • Active Speed Limit Assist (automatically adjusts speed based on posted limits)
  • Active Lane Change Assist (automatically steers into the next lane with a signaled lane change while using adaptive cruise control and Active Steering Assist)
  • Pre Safe Sound (Emits a tone that protects occupants’ hearing during an impact)
  • Magic Vision Control (Heated wiper blades with integrated washers)

During a day traveling on multiple Los Angeles freeways, the GLS’s ADAS worked well, aside from one, almost dangerous, error.

When traffic flows in L.A., it does so at about 80 mph. At one point, with the adaptive cruise control set to 75 mph, the GLS passed a speed sign notifying truckers that their speed limit was 55 mph. In response to this sign, the GLS actively initiated rapid braking on its own in an effort to bring the cruising speed down to 55 mph in a short span.

At first, the sudden braking action was a mystery. But I’ve experienced this technology before in other German SUVs, and I quickly realized the Active Speed Limit Assist had read the truck speed limit sign. While I understand and appreciate the sentiment behind this technology, it’s not suitable for American roads. The last thing you want to do on a fast-moving L.A. freeway is brake for no apparent reason. It’s a good way to inspire road rage in others or even cause another driver to rear-end your expensive Mercedes SUV.

I want to give a special shout-out to the Active Lane Keeping Assist technology. If you unintentionally wander from your lane, this technology is not screwing around about preventing a lane or road departure. Though it exhibits aggressive lane maintenance behavior, in my experience, its dramatic action is absolutely warranted.

2021 Mercedes-Benz GLS FAQ - Find the best Mercedes-Benz deals!

2021 Mercedes-AMG GLS 63 Cargo Area

Photo: Christian Wardlaw

How much cargo space does the 2021 Mercedes GLS have?

Behind its third-row seat, the 2021 Mercedes GLS provides 17.4 cubic feet of cargo space. Power seat-folding buttons are located in the cargo area, and with the third row folded flat, the GLS can carry 42.7 cubic feet of luggage. Maximum volume measures 84.7 cubic feet.

Does the 2021 Mercedes GLS get good gas mileage?

The GLS returns between 16 mpg and 21 mpg in combined driving, depending on the version you choose. The AMG GLS 63 averaged 17.1 mpg on the evaluation loop, beating its EPA estimate of 16 mpg.

Is the 2021 Mercedes GLS safe?

Typically, the National Highway Traffic Safety Administration (NHTSA) and the Insurance Institute for Highway Safety (IIHS) do not perform crash tests on expensive luxury and performance models. That’s why ratings for the GLS are unavailable. However, given the SUV’s recent redesign, full collection of safety technology, and a minimum curb weight of 5,467 pounds, it is likely to do a good job of protecting you and your passengers.

How much is the 2021 Mercedes GLS?

Prices range from $76,000 for the GLS 450 to $160,500 for the Maybach GLS, not including a destination charge of $1,050.

What are the 2021 Mercedes GLS competitors?

In the J.D. Power 2021 Initial Quality Study (IQS), the BMW X7 ranks highest in the Large Premium SUV segment. The Lexus LX and the Toyota Land Cruiser are the next highest-ranked models (in a tie).

In the 2021 APEAL Study, the BMW X7 ranks highest in the Large Premium SUV segment. The Cadillac Escalade and the Land Rover Range Rover are the next highest-ranked models.

Other competitors to the 2021 GLS include the GMC Yukon Denali and Lincoln Navigator.

Independent Expert Opinion - Find the best Mercedes-Benz deals!

2021 Mercedes-AMG GLS 63 White Rear Quarter View

Photo: Christian Wardlaw

It is a worrisome sign that just a year after a complete redesign, the Mercedes-Benz GLS ranks below rivals including the BMW X7, Cadillac Escalade, and Land Rover Range Rover in terms of its overall appeal. This is according to verified owners of the vehicles in question, as reported to J.D. Power. Evidently, luxury SUV buyers with a GLS parked in the garage simply are not as satisfied as the people who picked the BMWCadillac, and Land Rover.

Based on my experience with the GLS, it is nevertheless worthy of your consideration. The technology alone excites the geek in all of us, and its combination of size, power, and sophistication is exactly what buyers in this class expect. Plus, the GLS 63 and Maybach versions are especially compelling if you've got the money to burn.

Christian Wardlaw is a veteran digital automotive journalist with over 25 years of experience in test-driving vehicles. In addition to JDPower.com, his work has appeared in numerous new- and used-car buying guides, newspapers, and automotive industry trade journals.

The opinions expressed in this review are the author’s own, not J.D. Power’s.

No portion of these reviews may be reproduced, distributed, publicly displayed, or used for a derivative work without J.D. Power’s written permission. © 2022 J.D. Power

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