Mercedes-Benz GLC 350 d AMG Line 2017 first drive

Until recently, Mercedes' Mercedes-Benz GLC was available with a host of exotic trim inlays, colours, leathers and perfumes (yes, really). However, it wasn't possible to add a fifth and sixth cylinder to your diesel engine - it was the four-cylinder 220 d, pokier 250 d or, well, nothing. That's no longer the case, because with news that a full-fat AMG GLC 63 is on the way to join the lesser GLC 43, there's also the option of Merc's venerable V6 350 d.

Happily, you may pair your V6 diesel with each and any of the GLC’s trims, which means prices for the 350 d start at £42,140 for the SE model and top out at £45,630 for the range-topping AMG Line we’re driving here. That's around £6000 more than the equivalent 220 d, and £4500 more than the 250 d. Of course, ours being a press demonstrator, the as-tested price climbs to a whopping £53,570, the most notable addition being Merc’s air suspension (a £1495 option).

Shelling out for the V6 brings 257bhp and a healthy 457lb ft. Considering the price premium, those outputs are a distinguished but required step up from the brace of four-cylinders beneath the V6 in the model range. Naturally, economy takes a hit, forcing official average fuel consumption down to 47.9mpg and CO2 emissions up to 159g/km. Not particularly good news for a private buyer, then, nor the company driver sitting across from the bean-counter pitching his or her case for a six-cylinder car. 

Although the 350 d isn’t the GLC you choose if your main concern is keeping the company accountant onboard, it is the most luxurious, grown-up Mercedes-Benz GLC we’ve tried yet. Both Merc’s superb V6 diesel engine and the cosseting air suspension chassis are the reasons behind that.

There’s a reassuringly premium feel to the muscularity of this 3.0-litre unit. It swells stoutly at around 1600rpm and works effectively with Mercedes’ standard-fit nine-speed auto to provide confident in-gear flexibility - or a hot hatch-chasing 6.2sec 0-62mph sprint should the need arise. All the while, it remains easily the most refined of the diesel engines on offer to GLC buyers.

Similarly, the long-wave nature of the GLC’s optional adjustable air suspension pairs with this engine perfectly, providing sumptuous Comfort-mode waft at high speed and rounding off the majority of urban bumps well. It’s not without fault mind you, the odd sharp-pothole hole or rut capable of unsettling the body momentarily, especially at lower speeds when its stiffer Sports mode is employed.