One of the names given to the brand-new Mercedes-AMG GLC—2025 The Mercedes-AMG GLC63 S E Performance is the first sign that this powerful machine has become more complicated. The Hammer, a simple but useful tool, used to be AMG’s most famous object. You wouldn’t say that AMG’s new GLC is simple, but it works well.
The biggest difference between this group and the last is the source of motivation. That car had a 4.0-liter V-8 engine that was twin-turbocharged and managed to channel the power of AMG’s big naturally aspirated 6.2-liter V-8. Now, AMG has switched to a 2.0-liter turbo four, which cuts the number of cylinders and volume in half. But wait, don’t leave yet—it has 671 horsepower!
The M139l four-cylinder engine, which has a huge boost and can make 469 horsepower (236 horsepower per liter), works with an electric motor placed on the back to reach that high score. A 4.8-kWh battery powers the motor, which has up to 201 horsepower. The battery can be charged by either the engine or the cord, making this a plug-in hybrid. There is also an electric motor on the shaft that connects the compressor and turbine wheels. This motor turns on the turbo and keeps the snail turning when the driver lets off the gas. To power the e-motor and make the automatic stop-start system work, there is a 400-volt system. There is a nine-speed automatic transmission with a clutch pack instead of a torque converter, and the rear motor has its own two-speed drive. Last but not least, the 4Matic+ all-wheel-drive system can send power from the engine and e-motor to either axle in any ratio between 50/50 and 100% rearward. This is the engine from the 2024 C63, with a few small changes.
The bottom of this SUV has a lot going on as well. For the new GLC63, the old air springs have been replaced with steel coils, and the adjustable dampers have been retuned to give you more control. Also, there are active anti-roll bars, which need their own 48-volt power source. You can now turn with the back wheels. With a curb weight of almost 5,100 pounds, the brakes need to be strong, and they are. The front brakes have 15.4-inch discs and the back has 14.6-inch discs.
The GLC63 S E Performance “enables a previously unknown variety of driving experiences,” according to AMG’s head of vehicle development, Steffen Jastrow. This is why the steering wheel has an eight-way dial that lets you choose between eight different drive modes: Slippery, Individual, Battery Hold, Electric, Comfort, Sport, Sport+, and Race. There are seven powertrain settings (Reduced, Battery Hold, Electric, Moderate, Sport, Dynamic, and Race), three levels of adaptive damping (Comfort, Sport, and Sport+), and four AMG Dynamics levels (Basic, Advanced, Pro, and Master—the last one can only be used after turning off stability control). These levels change the all-wheel-drive system, the rear-wheel steering, the limited-slip differential, and the stability control. It also has a launch mode. The only thing it doesn’t have is the Drift mode from the C63. The driver can put two of the available elements on the left display circle of the steering wheel. There are two buttons on this circle that let the driver move through the options without using the touchscreen.
To get the most out of the powertrain, you need to put Boost mode on the left circle. This mode is only available in Race mode and lets the electric motor give its full 201 horsepower in 10-second bursts.
Motorsports driving is clearly one of the GLC63 adventures that no one knew about before. If you’re going to the Christmas tree, there’s also a Drag Race table. Or, if you’re on a road course, the GLC63 can save plans of the most important racetracks. For your track session, you can record and later download telemetry that shows speed, steering wheel angle, longitudinal, lateral, and vertical acceleration, slip angle, front and rear wheel angle, boost pressure, electric turbocharger power, engine output, torque, and speed, gear engine or transmission oil temperature, 12V battery voltage and current, HV battery charge level, voltage, current, and temperature, rear axle locking ratio, individual tire temperatures, and pre-load. Will anyone use this? “We don’t know how many of our customers are going to a racetrack,” says Patrick Roth, a product planner at AMG. Yet, “if you want to, you can do it.”
The electric-driving part is at the very opposite end of the range. The GLC63 can be driven in EV mode, and the motor is strong enough for highway speeds. However, if you push through the kick-down detent on the pedal, the gas engine will start up. If you want to drive a battery-electric car, this isn’t the right car for you. The EV range is only a few miles (12 kilometers on the European WLTP cycle, which is about six miles using EPA standards).
The GLC63 does have four levels of liftoff regen, ranging from none to one-pedal driving. However, you can’t choose the higher-than-normal levels until the battery is almost completely dead. Anyone can choose a higher-than-normal amount of regen, and it will work in all drive modes except Race. The brake regen doesn’t change no matter what amount of liftoff regen is chosen, and the modulation of the brakes felt very natural.
The ridiculous output numbers of this engine make it less powerful than rivals like the BMW X3 M Competition (503 hp, 479 lb-ft) and Alfa Romeo Stelvio Quadrifoglio (505 hp, 443 lb-ft). It sounds like too much, but the GLC63 is about 500 pounds heavier than the BMW and needs to be moved around. AMG says the time from 0 to 62 mph is 0.3 seconds faster than the old car’s. The old GLC63 S took 3.4 seconds to reach 60 mph, so this car should take 3.1 seconds. That would put it just ahead of the BMW (3.2 seconds) and the Alfa (3.3 seconds). If AMG’s new, very complicated drivetrain doesn’t seem to give it a big edge over its competitors, then why do it? It’s clear that AMG sees the move as a step toward the future of electric vehicles. “We’re an engineering company, and we want to develop,” states Roth.
When you drive the GLC63 S E Performance, though, you realize that this thing just works, despite how complicated it is.
It was how we felt after two days of driving mostly on empty mountain roads in the southern part of Spain. It was like the engine did everything you could ask for and more. As you might expect, the GLC63 can also take off quickly from a stop. You don’t even need to use the launch control. We changed between the more sporty drive modes by going through a long stretch of fast, sweeping turns and then tighter switchbacks. As we went around turns, the nine-speed automatic downshifted just in time to prepare for them, held in the lower gear for just the right amount of time, and quickly moved up as our speed rose.
When you’re on the highway and step on the gas, the acceleration doesn’t go crazy right away. The GLC moves forward on a wave of force from the engine’s many parts. It takes half a beat for the engine to gather itself. When driving, requests for faster speeds are met with a gentle rise in speed, rather than sudden drops in speed. The PHEV will easily switch between gas and electric power when going from a stop to a go at a low speed.
This electric four-banger should be enough for people who are new to AMG. But people who buy from the brand again might miss the loudness of its V-8s. There is a “enhanced sound” setting on the turbo four that is separate of the drive mode. It’s not terrible, but it can’t compare to the V-8’s deep, throaty rumble, especially at start-up.
The GLC63’s frame is just as complicated as its engine, which is a good thing. In any of the three modes, the steering avoids all the obvious problems. Its response doesn’t change wildly, and it’s neither too light in Sport+ nor too heavy in Comfort. Instead, it gives you expected responses and even a little feel. Some of the things that affect how much rear steer there is are the drive mode and the fact that we could feel it tightening the line during a set of moderately fast turns. But for most of our two-day drive, we couldn’t see its helpful hand.
What’s really amazing is the suspension. SUVs with a lot of power, like the X3 M Competition, tend to have rough rides. Not in this case. It is said that these adaptive dampers can be tuned for a bigger range of compression and rebound, and when combined with the steel springs, they offer a wide bandwidth. The Michelin Pilot Sport 4 SUV tires (265/40ZR-21 front and 295/35ZR-21 rear) don’t offer much comfort over rough terrain, but the handling never feels harsh or stiff. The cars we drove had standard active anti-roll bars that kept the heads from tossing back and forth. They also didn’t have any body roll.
