Mercedes-AMG GLC 63 review

Think of any type of car and there’s probably an SUV alternative – and that includes sports cars. Sports SUVs like the Mercedes-AMG GLC 63 offer physics-defying performance in an SUV package (at a price).

Very few of them can hold a candle to the GLC 63 in terms of outright acceleration, though. At the hands of our expert road testers on a private test track, the previous-generation version clocked the fastest 0-60mph and 0-100mph times of any SUV we’ve tested. (For all you Top Trumps fans, the numbers were 3.6 and 9.0 seconds.)

On paper, at least, its plug-in hybrid (PHEV) replacement – called (deep breath) the Mercedes-AMG GLC 63 S E Performance – goes one step further, with an even more outrageous 0-62mph time of 3.5 seconds.

This performance version of the Mercedes GLC is far from alone in the world of sports SUVs of course. There’s also the Audi SQ5, the Porsche Macan GTS, the exhilarating Alfa Romeo Stelvio Quadrifoglio plus M versions of the BMW X3 and BMW X4.

So, is the Mercedes GLC 63 the one for you? In this review, we’ll tell you what it’s like to drive, how comfortable it is and whether it’s practical enough for family life. And, even though it’s a £100,000-plus car, we’ll tell you how much it’ll cost to run.

There’s just one engine available in the GLC 63 – the 2.0-litre turbocharged unit from the Mercedes-AMG C 63 S – and it offers immense performance.

With 469bhp, it’s the world’s most powerful mass-produced four-cylinder engine. And as with the C 63, it’s joined by a rear-mounted electric motor for a combined output of 670bhp. Yet, as a PHEV, it has a bit of a split personality.

It lacks the menacing grumble of the previous-generation car's 4.0-litre twin-turbocharged V8, and you might even call it civilised. Certainly, if you twist the drive mode selector on the steering wheel to call up the EV (electric vehicle) mode, you won’t even wake the neighbours.

Indeed, it’s fairly hushed in most of its drive modes. Sport gives a pleasing rumble, but Sport+ pipes some artificial sounding exhaust noise into the cabin, which will delight some, but irritate others.

However, there’s no doubting the GLC 63’s straight-line performance, along with its thundering soundtrack as you pick up speed. If circumstances allow, it won't stop pulling until you reach its 171mph top speed.

Response from the accelerator is good, largely thanks to a turbocharger that uses an electric motor to fill any lulls from its performance. And you can’t overlook the impact of the 201bhp electric motor on the rear axle, either.

It’s fed by a battery designed in-house by AMG, takes inspiration from Mercedes Formula One cars, and works with a regenerative braking system that recharges the battery, so there’s always power available for hard acceleration. Unusually for a PHEV, the regenerative braking system allows one-pedal driving.

The downside is that there’s not a great amount of feel through the brake pedal, and you have to really work your left leg to slow the car at speed. The (admittedly less potent) Range Rover Sport PHEV is far better in that respect.

The nine-speed automatic gearbox shuffles between gears quickly and smoothly. It’s possible to do this manually using a pair of beautifully crafted paddles, but we found it a bit too eager to slip back into automatic mode.

For an SUV that offers such impressive performance, the GLC 63 has a surprisingly supple ride on the sort of smooth roads we've driven it so far.

Even in its more aggressive drive mode settings, it takes undulating road surfaces in its stride. And despite the car’s wide low-profile tyres on 21in alloy wheels, there’s not a great deal of road noise. It’s certainly comfier for the most part than the Alfa Romeo Stelvio Quadrifoglio (QV).

The handling impresses, too. The steering is a bit inconsistent in its weighting and response – unlike on the laser-guided Stelvio QV – but you soon learn to place the nose of the GLC 63 accurately enough. That could in part be due to the car’s speed-sensitive steering, although in Sport and Sport+ modes the steering wheel provides noticeably more feedback.

There’s four-wheel steering, too, and it makes a huge difference, improving stability, especially through fast, sweeping corners. Below 62mph, the rear wheels turn 2.5 degrees in the opposite direction to the front wheels to reduce the car’s turning circle, boosting round-town manoeuvrability. Above 62mph, they turn in the same direction as the front wheels by up to 0.7 degrees.

The GLC 63’s main drawback as a performance car is that it always feels like the big heavy brute it is – both in terms of its significant weight and its dimensions.

While the Stelvio QV and the Porsche Macan GTS shrink around you, the GLC feels almost like a muscle car in comparison. Of course, for many, the hilarious straight-line speed and glorious noise will be enough, but if you like the challenge of a good set of corners, the rivals will put a much bigger smile on your face.

Driving overview

Strengths Remarkable acceleration; four-wheel steering inspires confidence when cornering at speed

Weaknesses Brakes require working hard; feels heavy when cornering

To create the GLC 63's interior, AMG has given the regular Mercedes GLC a makeover. That includes adding adjustable ambient lighting, a flat-bottomed sports steering wheel with various drive mode selectors, and electrically adjustable figure-hugging sports seats in a variety of racy materials.

And, instead of regular analogue dials, you get a 12.3in digital instrument cluster with AMG-specific displays. Depending on the mode, the display can look a little overwhelming, but the graphics are impressively sharp and it’s all fairly easy to navigate using the buttons on the steering wheel.

Thanks to a multitude of electric adjustments for the seat and steering wheel, it’s easy to find a driving position that suits you, regardless of your height. The seats can drop fairly low so you can have a sporty driving position, or lift higher to make the most of the GLC’s commanding driving position.

The swooping design of the dashboard makes the driver and front passenger feel cocooned, and the controls are no more than a short stretch away.

Fit and finish are very good, and you’ll have to work hard to find any scratchy-feeling plastics. The smart air vents are a particular design highlight. It feels more special than a Porsche Macan and more plush than the rather flimsy interior in the Alfa Romeo Stelvio Quadrifoglio.

Most functions in the GLC 63 are operated using a portrait-oriented central touchscreen. The graphics are crisp and the system is highly responsive to touch. Backed by Mercedes’ MBUX software, its Siri-style voice command system is surprisingly effective even if, like Siri, it sometimes interrupts mid-conversation.

It’s disappointing that the climate controls are on the touchscreen, rather than you getting physical buttons, but at least they’re always visible. Overall, the system is good – although BMW’s iDrive system is less distracting to use when driving.

Interior overview

Strengths Beautiful interior styling; cocooning feel from the driver’s seat

Weaknesses Frequent interruptions from voice control; no physical climate controls

The Mercedes-AMG GLC 63 is just as spacious as the standard GLC, which means there’s plenty of room for four adults in comfort (five at a slight squeeze).

There’s lots of forward-backward adjustment for the front seats, allowing tall passengers to get comfy, and even on versions with a panoramic roof, there’s lots of head room.

It’s equally spacious in the rear, and there should be no complaints from a six-footer sitting behind another six-footer, let alone three children in the back.

Overall, the GLC 63 is better than the Porsche Macan for passenger comfort – although anyone sitting in the middle rear seat will have to place their feet on or either side of a wide hump in the floor (that's true of most sports SUVs).

There’s no shortage of storage space, with large door pockets and a huge cubby in the centre console that can hold two bottles of water, plus phones and keys. The glovebox isn’t huge, though.

The rear seats split and fold in a 40/20/40 arrangement, allowing longer items such as skis to be carried alongside two rear-seat passengers. The boot itself is accessed via an electrically-operated boot lid.

From there on, the boot is a little compromised. At 470 litres, it roughly matches the Audi SQ5's, but is smaller than the Alfa Romeo Stelvio Quadrifoglio's. Like PHEV versions of the Jaguar F-Pace, it has a raised floor that slopes down towards the boot opening.

We’ve not tried to fill the boot with carry-on suitcases to test its practicality, but we'd expect it to take about seven of them.

Practicality overview

Strengths Comfortable and supportive front seats; plenty of rear leg room for two adults; lots of head room even when the panoramic roof is fitted

Weaknesses Hybrid batteries compromise boot space; wide transmission tunnel rob middle-seat rear passenger of foot space

Let’s be honest, you’re not going to buy a Mercedes-AMG GLC 63 if you’re looking to save the planet or money.

Indeed, fuel economy and the electric driving range are both poor by normal standards, although it's worth remembering the car’s battery has been designed specifically for fast power delivery, not to drive long distances on electricity alone. 

All models cost at least six figures, and no version is financially attractive as a company car (they sit in the top bracket for BIK tax).

Then there’s the fuel economy, which officially stands at around 37.7mpg. As ever with a plug-in hybrid, if you can make efficient use of the 7.4-mile electric driving range, you might come close, but you’ll need a featherweight right foot or judicious use of the car’s EV driving modes and impressive brake regeneration to do it. We'd expect single-figure fuel economy if you make full use of the GLC 63's performance.

The 6.1kWh PHEV battery can be charged using a 3.7kW charger, or more likely through the car’s brake recuperation technology. 

Mercedes as a brand finished a disappointing 24th place out of 32 manufacturers in the 2023 What Car? Reliability Survey. The current Mercedes GLC didn’t feature in the rankings, but the previous generation car came 11th out of 24 large SUVs ranked. A three-year/unlimited-mileage warranty and three years of breakdown cover are standard – a similar package to that offered by most rivals.

As you’d hope for the price, you get plenty of equipment on all versions, including air suspension, 21in alloy wheels, heated front seats, dual-zone climate control, augmented-reality navigation and rear-wheel steering.

Night Edition trim adds a panoramic roof, a Burmester stereo upgrade, black exterior styling and sportier seats.

Edition 1 cars feature yellow styling accents inside and out and extra bits of carbon. We think the entry-level model is the pick of the range.

All models also come with automatic emergency braking (AEB). There’s also a tyre-pressure monitoring system, seven airbags and a system that can detect if you’re getting drowsy on long journeys.

Costs overview

Strengths Lots of standard equipment; decent on-paper economy given the performance on offer

Weaknesses Six-figure price tag

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