Goodbye 4cyl: the Mercedes-AMG GLC 53 gets a ‘high-revving’ 3.0-litre straight-six

This is the new Mercedes-AMG GLC 53. It is a performance SUV – because of course it is – featuring a heavily revised version of AMG’s 3.0-litre turbo petrol engine. There is much power. Modes. And more… cylinders.

Yes folks, it’s a hearty farewell to AMG’s largely unloved 2.0-litre four-cylinder unit that saw service in the GLC 43 and GLC 63 (in various outputs, of course). Replacing both of those cars in the HotGLC lineup is this “comprehensively redeveloped” 3.0-litre straight-six petrol unit with “a strong appetite for revs”.

AMG has gone to (party) town on it, too. There’s a new cylinder head with improved intake and exhaust ports, a new intake cam, a new intake system that’s bigger, and a new intercooler. The turbo gets 1.5 bar of boost, while the electric compressor “can now operate almost continuously for a longer period”.

As a result of this AMG-tweakery, total power now sits at 443bhp and 443lb ft, rising to 472lb ft in overboost. That’s sent to a nine-speed ‘Speedshift’ auto ‘box and fully variable all-wheel-drive to allow for a 0-62mph time of just 4.2s and a limited top speed of 155mph.

Naturally, there are modes – slippery, comfort, sport, sport+, individual – and it’s able to completely decouple the front axle when your pants aren’t on fire to make it a rear-drive-only GLC. There’s an e-diff on the back axle (and rear-axle steering) for the first time, too, and a starter-generator snuggled inside the gearbox for start-stop goodness and a bit of additional boost.

Brakes? Big ones, measuring 390mm up front with four-piston calipers bolted over them. The rears are 360mm units with single piston calipers.

Noise? A big one, apparently. “The powerful and emotional engine sound is further enhanced by a new exhaust system,” says AMG. “The characteristic crackling on throttle lift-off creates goosebump moments, as do AMG typical misfires and the bassy sound during strong acceleration.”

AMG will offer a ‘Golden Accents’ pack for the first year of the GLC 53’s life, which – surprise! – adds detailing in ‘techgold’, while the ‘Night Package’ adds high gloss black here and there.

“With the new GLC 53, our goal was to make its Affalterbach DNA even more tangible – with more emotion, more character, and even more fun to drive,” said AMG boss Michael Schiebe. “To achieve this, we have significantly upgraded our six-cylinder engine.”

Does this mean the C63 will also bin the largely unloved 2.0-litre four-cylinder hybrid unit and get this “comprehensively redeveloped” 3.0-litre straight-six petrol? Hmm…