2019 Mercedes-AMG GLS63 – Road Test Review – By Matt Barnes

With a $125,000 base price, the Mercedes GLS 63 AMG is out of range for many people.

For those who have the wherewithal and need to haul six people, it is an excellent — and perhaps only — choice.

Featuring a hand assembled AMG 5.5 liter twin turbo (Mercedes calls it a biturbo) V8 with 577 horsepower and 561 torque, the GLS AMG has only one three-row performance competitor: the 475 horsepower Dodge Durango SRT 392.  [Audi is not bringing the diesel SQ7 to the USA.]

When it comes to luxury, the Mercedes is at the top in this class. Everything inside looks and feels like it’s made of the highest quality materials. The dials are heavy and solid, and every turn is deliberate. Every surface is soft touch, the infotainment system was easy to use and well-integrated, and the seats are adjustable to be comfortable for nearly anyone.

As is common with Mercedes AMG vehicles, the exterior was understated for what was hiding underneath. There are only a few items that are telling of the monster within. Pictures don’t really show the true beauty. It’s a vehicle that must be appreciated in person.

Our test vehicle came with the Bang and Olufsen upgraded sound system. The system provides good sound quality and cool tweeters in the front doors, but there are better quality sound systems in vehicles that cost half what the GLS63 does.

The seats are comfortable, but not so much they put you to sleep. The front seats include three different massage settings, which don’t rival a real hands-on massage, but nonetheless provide some relaxation while driving. The front seats are heated and cooled while the middle row seats are heated. Both the middle and rear rows accommodate car seats well. Adults may have trouble getting comfortable in the rear seats for longer drives, but the kids should have no problem back there.

The front seats also provided heated and cooled cup holders which help keep beverages at the desired temperature for longer times. It’s very easy to see what setting the cupholders are in, as they will glow yellow when off, blue when cooling and red when heating.

The front center arm rest is split down the middle and opens sideways. This makes the opening motion much shorter than one with hinges at the back, but it also blocks access into the storage area enough that it’s difficult to see and reach inside without adjusting the seating position.

The center stack is easy to navigate with clearly marked buttons and controls. Everything that needs to have a physical button has one, which isn’t true for all vehicles. It also has clearly marked buttons for the different drive modes for the suspension height, dampers and transmission. Switching between the modes is as easy as twisting a dial or pushing a button. Having physical buttons saves time searching through the infotainment system for a seat heater or sport suspension setting.

The infotainment system takes a little getting used to for those not familiar with it. We found ourselves occasionally hitting the touch pad and changing screens when we didn’t want to. The system works fast and is fairly intuitive to navigate. Spend an hour or two playing with the system while parked and it will be a breeze to manage while driving.

At normal driving speeds, it remains very composed and easily manageable. The twin turbo, or bi-turbo as Mercedes calls it, never feels stressed. Accelerating from a stop to merge onto a freeway is effortless. Accelerating to pass a slow-moving vehicle rarely requires a down shift, and with the quiet interior it’s easy to exceed the speed limit without knowing it.

Get on the gas pedal and the beast really comes alive. The engine remains smooth from idle to redline, but when revving in neutral it has enough power to shake the roughly 6,000 lb SUV. We tested the vehicle at 4,600 feet above sea level where the air is a bit thinner. Due to the turbos, the thinner air had little effect on the performance of the engine. We were able to get a 4.9 second 0-60 time, which is just a bit slower than the advertised 4.5 second time.

Keeping things smooth is the highly refined 7-speed transmission. It reacts quickly to any changes from the driver and, when placed in sport or sport+ modes, shifts incredibly quick. Also, when in one of the sport modes, the quick down shifts provide for wonderous sounds from the exhaust.

The Pirelli P-Zero tires are wide with short sidewalls which provide excellent acceleration and handling characteristics. With a normal vehicle, that would equate to a rough ride, but with Mercedes’ adjustable dampers and air suspension, the ride remained smooth. With the Active Curve System’s electro-hydraulically controlled stabilizer bars, the suspension also kept the SUV level in the corners with minimal body sway for something so massive.

The stop/start technology didn’t help us save much fuel as the system only activated a couple of times during our drives. This probably has more to do with the settings we were using than anything else. Of course, the poor fuel mileage of 13.8 that we averaged over 200 miles was more likely caused by our heavy foot. The EPA estimated ratings are 13/18/15, and had we been able to control our need for speed, would have been right on, as we regularly saw 20 mpg at freeway speeds. The 26-gallon fuel tank should help alleviate any range issues from the lower fuel mileage.

Something that we really like about the GLS is that it drives much smaller than it is. It is easy to navigate through tight parking lots and to pull into and out of stalls. Visibility is good everywhere, but the rear corners, as the windows are smaller in the back and the D-pillar is quite thick. Most other spots can be easily seen just by moving a little to get around the B-pillar on both the driver’s and passenger’s side. It is also equipped with a 360° camera, which eliminates all blind spots.

Our test vehicle wasn’t optioned with the trailer hitch receiver, but with a tow rating of 7,500 pounds, the 561 foot-pounds of torque and 4-Matic all-wheel drive system, it would make for a good vehicle to pull a water sports boat down to the lake.

The headlights are very bright and light up the road exceptionally well. The brights don’t extend as far as we’d like, but that might just be because the normal beams are so good. The exterior lighting at night is great for approaching and entering the vehicle. It also projects a Mercedes logo onto the ground, just in case you forget what you are driving.

There are plenty more features on GLS63 AMG that we didn’t cover. It comes fully loaded by Mercedes standards, which are pretty high. The driving experience was nothing short of amazing with silent and smooth highway cruising, and more performance than is ever needed from a vehicle this size. In the week we spent with the GLS63, the only thing we think Mercedes needs to upgrade is the sound system.

Handling, ride quality, power, cargo volume, passenger comfort, drivability and even the fuel mileage were as good or better than expected from this class of vehicle.

For a truck that has it all, and does it all, look no further than the GLS63 AMG.

Read Matt’s other drive reviews over here!