Mercedes-Benz GLB-Class vs Mercedes-Benz GLC-Class

What's the difference?

It’s easy to say the GLB35 doesn’t deserve to be called an AMG when looking at its credentials on paper, but get behind the wheel and it’s evident Affalterbach played a key role in making it feel as special to drive as it should be.

The GLB35 has all of the great qualities of the GLB250 and other GLB variants, but successfully adds a performance focus to make for an even more compelling package.

Indeed, the GLB35 proves you can pretty much have it all.

Like I said right from the start, this new, hybrid version of the AMG GLC63 is technically superior to the model it replaces in every meaningful way. It is faster, more powerful and more fuel efficient and therefore a better performance SUV than the model it replaces.

Is it a better model than the one it replaces? Ultimately that will come down to how much stock you put into the soundtrack and your feelings on an AMG not powered by a V8 engine.

Because if you can see past that, then the AMG GLC63 is an absolutely fantastic performance SUV. Not only does the new powertrain make it faster in a straight line, but the chassis is very well-balanced, making for an engaging driving experience.

For those who can look past the smaller engine they will be rewarded with an incredibly fast and rewarding-to-drive member of the AMG family.

Note: CarsGuide attended this event as a guest of the manufacturer, with travel, accommodation and meals provided.

With the boxy and therefore rugged-looking GLB laying some great foundations, it’s no surprise the GLB35 looks pretty damn good – to these eyes, at least.

Being an AMG model, it stands out from the crowd with an aggressive body kit, with the chunky bumpers, aerodynamic roof spoiler and racy rear diffuser all unique alongside the now-signature Panamericana grille insert.

A set of 20-inch alloy wheels with 255/40 tyres ups the ante at the side, where the carryover black plastic wheel-arch and skirt cladding serves as an obligatory reminder that this is an SUV.

Also of note are the nicely designed LED headlights and tail-lights, which literally light the way, but there’s no getting past the bespoke diffuser element, which integrates the sports exhaust system’s dual 90mm tailpipes.

Inside, the GLB35 is a technological tour de force, with a pair of 10.25-inch high-resolution displays proudly sitting side by side atop the dashboard, with one the central touchscreen and the other the digital instrument cluster.

Both are powered by Mercedes-Benz’s MBUX multimedia system, which arguably remains the best there is today thanks its speed and breadth of functionality and input methods.

The GLB35 is also properly premium. Lugano leather upholstery covers the seats and armrests, while Nappa trims the sports steering wheel. Even the door shoulders and inserts get ‘cow hide’, although theirs is of the artificial variety.

Soft-touch materials are used for the upper dashboard, leaving hard plastics to the lower sections, which is what you’d expect for the price.

While the black headliner makes for a dark cabin, brightness comes from the metallic trim used throughout, notably on the steering wheel, dashboard, doors and centre console. And let’s not forget the pop of colour provided by the addictive ambient lighting.

And mercifully, scratch- and fingerprint-hungry gloss-black accents are limited to the surrounds of the turbine-style front air vents, dual-zone climate controls and centre console.

Unique to the GLB35 are Carbon Structure trim and stainless-steel sports pedals, just in case you forgot you weren’t driving a regular GLB.

The GLC63 is unmistakably an AMG from the moment you first lay eyes on it. That’s thanks to the AMG-specific elements, starting with the grille with vertical strikes and the AMG crest on the bonnet; which is now a signature item for the performance sub-brand.

The GLC63 is also fitted with the Night Package II design kit; this adds a darkened grille and black chrome badging to further enhance its visual appeal.

The AMG-specific alloy wheels and more aggressive stance do mean the GLC63 stands out from the rest of the GLC range, helping it look fast even when it’s standing still.

Measuring 4650mm long (with a 2829mm wheelbase), 1845mm wide and 1660mm tall, the GLB35 is more like the GLC43 in size than the GLA35, making it a mid-size SUV despite its small underpinnings. And that is good news for practicality.

Cargo capacity with the 50/50 split-fold third row stowed is more than solid, at 565 litres (VDA), but it can be increased to a cavernous 1800L with the 40/20/40 split-fold middle bench also not in use. If six or seven passengers are onboard, though, there’s very little room to move.

Nonetheless, the boot is still well packaged, featuring a huge aperture, no load lip, and a flat floor, which make loading and unloading bulkier items a hell of a lot easier. And even the load cover can be stored underfloor when out of action. How good.

There are also four tie-down points, two bag hooks, a side storage net and a 12V power outlet on hand to make matters even easier, while the rear seats can be stowed from the boot.

While we’re on the topic, Mercedes-Benz says the third row can accommodate passengers up to 168cm tall, with the middle bench able to slide fore and aft by up to 140mm.

Yes, I'm too tall, at 184cm, but I can still sit in the very back, although not in total comfort. All in all, about a centimetre of legroom and negligible headroom and toe-room are on offer there for me.

That said, getting in and out in the first place is the real challenge here, with the middle bench unable to tumble forward for easy ingress and egress. Yep, you’re not going to look smooth either way. Children can deal with it, but adults won’t be thrilled.

Therefore, the middle bench is the place to be, even when it’s slid all the way forward. Behind my driving position, it offers about a centimetre of legroom, but this can be increased to several inches by sliding it all the way back.

Either way, plenty of toe-room is available alongside more than an inch of headroom. The latter is more impressive when you consider that’s what you get with the standard dual-pane panoramic sunroof fitted.

Even better, the second row can seat three adults at a pinch, partly thanks to the low transmission tunnel, which means there’s the right amount of space for six fully grown feet across the two footwells. It goes without saying children will again be fine.

Speaking of which, four ISOFIX and five top-tether anchorage points are on hand for fitting up to four child seats across the second and third rows, which makes the GLB35 a serious option for families that like to be sporty.

There are plenty of in-cabin storage options, with the large central storage bin featuring a pair of USB-C ports, while the glovebox is also quite useful, even if it is oddly shaped. And there’s also a sunglasses holder in front of the rearview mirror.

The centre console’s cubby isn’t really designed for storage, with it basically taken up by two cupholders, another USB-C port and a wireless smartphone charger.

The front door bins can accommodate one small and two regular bottles each, which is great, while their rear counterparts can take one small and one regular apiece.

Second-row occupants also have access to a fold-down armrest with another pair of cupholders, but being of the retractable variety, they’re flimsy.

These passengers also have two USB-C ports, with the pair folding out below a small cubby and air vents, which are found at the back of the centre console. Storage nets are also fitted on the front seat backrests.

And don’t worry; the third row gets in on the action, with two cupholders (one regular, the other small) splitting the seats, which have individual USB-C ports and device straps to the sides.
 

Inside the GLC63 is clearly a derivative of the rest of the range, with its C-Class-inspired design and layout, but there’s enough AMG-specific elements to ensure it looks and feels special. This starts with the AMG steering wheel, which comes not only with a thick rim wrapped in Alcantara, but also some AMG special dials to adjust the various performance settings for the powertrain, suspension and transmission.

Then there are the AMG-specific seats, which look good and offer good support for the driver and front seat passenger. The rear seats offer decent space for what is a mid-size SUV, with room enough for two adults or teenagers or three smaller kids.

Those in the back aren’t particularly well looked after though, with only rear air-con vents and small door pockets but no USB charging ports or other small item storage.

The boot is 590 litres, down from 620L in the rest of the range, thanks to the addition of the rear-mounted electric motor. There’s also no room for the temporary spare the rest of the GLC range gets and instead you have to make do with a puncture repair kit.

The power and torque figures aren’t the only numbers that have risen sharply, with the GLC63 clearly impacted by a double whammy of inflation and the usual new-car price rise.

The GLC63 now starts at more than $191,814 for the SUV and $198,415 for the Coupe, which represents a nearly $30k increase over the old V8-powered model, which was priced at $164,600 just two years ago. Even for luxury car buyers that’s a big jump, especially when you’re trying to convince people of the merits of the four-cylinder powertrain. 

That also means it's more expensive than all of its key competitors, including the BMW X3 M Competition, Maserati’s Grecale and the outgoing, petrol-powered Porsche Macan GTS.

To help explain some of this price increase Mercedes-Benz Australia has opted for a high level of standard specification for local cars. Standard equipment includes 21-inch alloys, AMG composite braking, a panoramic sliding sunroof, a unique AMG steering wheel, power-adjustable sports seats in Nappa leather, a head-up display, dual-zone climate control, wireless smartphone charging and a Burmester 3D Sound system.

Also included is the AMG Track Pace suite, for those who want to unleash their GLC on the racetrack.

There’s also a limited run, AMG Edition 1 Package available too, for an additional $12,900. On the outside you get Manufaktur graphite grey magno paint, foiling with colour gradation and large AMG logo on the sides, an AMG Aerodynamics Package, unique alloy wheels with Edition 1 and AMG branding, yellow brake calipers and an AMG fuel filler cap in silver chrome with AMG lettering. 

Inside there’s AMG Performance seats, AMG Nappa leather in black with yellow contrasting stitching, AMG illuminated door sills,  carbon-fibre AMG trim highlights, yellow seat belts and a unique AMG Performance steering wheel wrapped in carbon-fibre and microfibre.

The GLB35 is powered by an uprated version of the GLB250’s 2.0-litre turbo-petrol four-cylinder petrol engine, with the AMG-fettled version producing a more substantial 225kW of power from 5800-6100rpm and 400Nm of torque from 3000-4000rpm (up from 165kW/350Nm).

This version is also matched to an eight-speed dual-clutch automatic transmission as well as Mercedes-AMG’s front-biased but fully variable 4Matic all-wheel-drive system.

Thanks to this combination, the GLB35 can sprint from 0-100km/h in just 5.2 seconds with launch control enabled, while its electronically limited top speed is 250km/h.

This is what lies at the heart of the AMG GLC63’s success or failure. As I mentioned at the beginning, the previous generation’s 4.0-litre twin-turbo V8 has been replaced by an F1-inspired plug-in hybrid powertrain.

But don’t think that means AMG is suddenly focused on efficiency over performance. When AMG says the powertrain is inspired by the brand’s success in Formula 1 racing, what it means is the battery and electric motor provides a significant performance boost to support the internal combustion engine, not just save fuel.

To that end the combination of the turbocharged 2.0-litre four-cylinder petrol engine and the rear-mounted electric motor produces an impressive 500kW and 1020Nm. That’s a massive jump over the 375kW/700Nm made by the outgoing V8.

The GLB35’s fuel consumption on the combined-cycle test (ADR 81/02) is 8.3L per 100km, while its carbon dioxide emissions are 186 grams per km. All things considered, both claims are pretty decent.

In our real-world testing, though, we averaged a high 14.1L/100km over 75km of driving split between highways and country roads, so not your typical mix, then. A heavy right foot also played into that result, so expect a better return after a regular run.

For reference, the GLB35’s 60L fuel tank can be filled up with 98RON petrol at minimum.

Mercedes makes no secret that the battery is designed for performance, not saving fuel. It only has a 14km EV range but can recharge quickly on the move to provide a power boost when needed.

But despite all that, the GLC63 is actually significantly more fuel efficient than the old V8, using a claimed 7.3L/100km, which is a massive 4.9L/100km improvement over the old model. Although, on our day-long test drive we didn’t manage to come close to that claimed figure and instead saw returns around 11L/100km, albeit after a lot of spirited open-road driving.

Don’t let the GLB35’s family friendliness fool you, this is an SUV that can get up and go.

The engine’s extra power and torque over the GLB250 are immediately felt behind the wheel, with the GLB35 accelerating with the vigour of an all-wheel-drive hot hatch, which makes sense given their similar claims.

And if you have one of the sportier drive modes engaged, the booming noise generated is also special – even if a lot of it is of the artificial variety, pumped into the cabin to make occupants feel like things are getting serious.

What is genuine, though, is the well-rounded transmission, which is characteristically quick with its upshifts. At the same time, it’s also relatively smooth, even at low speed, which has proven to be a challenge for dual-clutch units over time, but not here.

To earn the AMG badge, the GLB35 goes even further with other mechanical upgrades, including sports tunes for the suspension and steering.

Specifically, the GLB35’s independent suspension set-up not only consists of MacPherson-strut front and trailing-link rear axles with adaptive dampers, but also introduces new steering knuckles, transverse control arms on the front axle, and a stiffened subframe.

The resulting ride is actually quite good. Yes, the extra firmness over the GLB250 is noticeable – particularly in the sportier drive modes that stiffen the adaptive dampers all the way – but it’s by no means a deal-breaker.

That said, it’s worth noting our test vehicle was fitted with the optional 21-inch alloy wheels ($1990), so the GLB35’s like to ride even better on its standard package.

This is remarkable considering the handling improvements made, with the GLB35 managing body roll and pitch better than the GLB250 when pushing hard into and around corners, coming out of which grip is plentiful thanks to the all-wheel-drive system.

Thankfully, the standard-fit high-performance braking package consisting of 350mm front and 330mm rear discs with four- and one-piston callipers respectively helped it wash speed away with ease when attacking the twisty stuff with intent, even with 1857kg (kerb) to deal with.

Also on hand is electric power steering, which is speed-sensitive and has a variable ratio in the GLB35. Basically, it’s quicker when you want it to be, remaining on the lighter side in hand until you engage one of the sportier drive modes and weight is increased markedly.

Anyone who still believes in the adage ‘there’s no replacement for displacement’ hasn’t driven a modern turbocharged and hybridised engine. The GLC63 is a demonstration of the metaphorical and literal power of modern technology, combining an extremely efficient and potent internal combustion engine with an electric motor to make enormous real-world performance.

To be blunt, the GLC63 feels like a rocketship out of corners, launching with a ferocity and relentlessness the old V8 simply can’t match. It shouldn’t come as a surprise, a mid-size SUV with 1020Nm was always going to have plenty of performance, but even so it’s a shock to the system every time you give the GLC63 full throttle. Officially AMG claims it takes just 3.5 seconds to run 0-100km/h and has an electronically limited top speed of 275km/h - mighty impressive figures for a five-seat mid-size SUV.

To help get all that torque to the road, AMG deploys torque distribution technology that allows for it to be split an even 50/50 front/rear all the way to 100 per cent to the rear tyres.

Other technologies deployed to enhance its handling include AMG Ride Control suspension with adaptive damping and rear-axle steering. There’s also eight AMG Dynamic Select driving modes and four AMG Dynamics settings (Basic, Advanced, Pro and Master), so it’s a complex vehicle that is designed for the enthusiast.

While it’s easy to drive around town, once you get out on the open road you can really get a sense of the GLC63’s performance potential. Beyond just its powertrain the suspension offers good body control and the rear-axle steering helps it feel agile and responsive. 

It’s not perfect though. At times the complexity of the system does lead to some hesitation when you put your foot down. It certainly lacks the linear power delivery of the old V8 and makes for a slightly trickier driving experience at times.

As for the sound, which is one of the biggest elements missing from the V8, Mercedes has added AMG Real Performance Sound, which features a pressure sensor in the exhaust that picks up on the engine note and plays it through the speaker system. It certainly helps make for a louder, more noticeable engine noise, but it still sounds more like an A45 than the previous GLC63 and for many would-be buyers, that’s a major turn-off.

The GLC63 comes standard with a comprehensive suite of safety features including 'Distronic' (Mercedes’ name for adaptive cruise control), 'Active Lane Keeping Assist', 'Blind Spot Assist', 'Traffic Light Assist' and 'Adaptive Highbeam Assist'. It also includes Mercedes’ 'Pre-Safe' accident anticipation system - which pre-tensions the seat belts and will even play a white noise to protect your ears if it senses a crash is imminent.

A parking system that includes a 360-degree camera and active parking assist is also included.

The GLC range was awarded a five-star ANCAP rating in 2022, which pre-dates the latest testing protocols, so doesn’t provide a like-to-like comparison for vehicles tested after that date.

As with all Mercedes-AMG models, the GLB35 comes with a five-year/unlimited-kilometre warranty, which currently sets the standard for the premium market. It also comes with five years of roadside assistance.

The GLB35’s service intervals are long, at every 12 months or 25,000km (whichever comes first). Better yet, it’s available with a three-year/75,000km capped-price servicing plan, but it costs $2750, with the third visit alone incurring a $1300 charge.

The GLC63 is covered by Mercedes Australia’s usual five-year/unlimited kilometres warranty.

As for maintenance, Mercedes offers service plans, spanning three to five years. Three years will cost you $5025, $6455 for four years and five years is priced from $7180. Servicing intervals are 12 months or 20,000km, whichever comes first.