2025 Mercedes-Benz E450d (S214) | UK Review
Big wagons with large diesel engines have drastically fallen out of favour - pity
What you’re looking at here is not a car - it’s a time machine. It’s a Mercedes-Benz with a three-pointed star proudly on the nose, for starters, which doesn’t seem to have happened for ages. It’s also an estate car - a rarity on its own - that doesn’t claim to be anything else: there’s 615 of space in the back of this conventionally styled E-Class wagon, or a whopping 1,830 with them down. When did you last read about one of those? It’s painted silver, rides on normal wheels, and is powered by a 3.0-litre combustion engine - with a 4,500rpm redline.
Yep, it’s a diesel E-Class wagon. The one you thought might have dropped off the configurator in the wake of, well, everything. Not just any black-pump Benz, either, as the four-cylinder 220ds launched with this W214 era; this is a 450d, complete with six cylinders, as much power as an Audi S5, and enough torque to pull the pyramids out of the ground. It’s perhaps the last of a dying breed, a throwback to when diesel was king and, surely, a welcome niche offering as opposed to another silly coupe SUV. No longer is there an A6 or 5 Series equivalent - the E-Class is the last remaining six-cylinder diesel wagon from the German big three. So what’s it like?
Traditionally pitched (and specced this time around) the E450d might be, but the engine is anything but old hat. While the OM656 is a familiar code, having first debuted in the last S-Class, the straight-six now benefits from mild hybridisation, the D30T RM and TM derivatives arriving last year with a 48v integrated starter generator and a Borgwarner eBooster compressor to further eliminate lag from the turbos. That’s in addition to the variable valve lift control, dynamic multi-way exhaust gas recirculation and near engine exhaust gas after treatment the 656 launched with - which won’t make much sense to the layman. What will make sense is that, officially, it’s possible to coax 45mpg out of 2.1 tonnes of E-Class wagon. Oh and it'll reach 62mph in 5.0 seconds, thanks to 367hp and 553lb ft of torque, which feel pretty persuasive for the ultimate family estate, especially alongside 165g/km. And range, of course: a standard 66-litre tank at let’s call it 40mpg is almost 600 miles to a fill.
It doesn’t take long behind the modest wheel of an E450d to be reminded of what’s so good about a big diesel. Even with petrol engines now mimicking a lot of their characteristics and EVs accelerating faster than fingers can be clicked, that sustained surge from little more than idle still means an identity all of its own. For certain E-Class diesel models a ‘Sporty engine sound’ is included, albeit not for our test car, though the straight-six snarl as standard really did resemble an inline petrol with a low rev limit. The smoothness is uncanny, the 450d feeling for all the world like it fuels from the green pump, yet with the pulling power of two engines. It’s been a long time since less than 2,000rpm produced such meaningful performance, that willingness at the first thousand operating revs (the mild hybrid side can contribute up to 184lb ft from just 1,200rpm) being really impressive. Extended further, the E-Class is more than willing: it does that fast diesel thing of appearing to consume each gear as fast as the preceding one, making for a torrent of acceleration that never lets up.
Something all-electric will make the task even easier, of course, though not nearly as interesting. Seeing how high a gear it’ll pull in, how few revs it requires, how many miles per gallon can be squeezed out in an average speed check - the novelty of compression ignition never seemed so riveting. Having faced the EV road trip angst recently, to sit at a cruise and watch the range climb was a welcome return. The nine-speed auto that perhaps doesn’t always suit the sportier applications is the ideal fit for such a peak torque monster, always with the right ratio and never too keen to kickdown. Having that mild hybrid assist means that boundless, effortless feel of a big diesel engine is only further enhanced. Without much effort at all, you’ll be much further away than intended. And very content.
Helps, too, that the rest of the E-Class package is so sumptuously sorted. The 450d is the only model in the range with standard air suspension, which will be one of the reasons why it costs so ruddy much, but it does lend the 450 a mellow, refined gait that matches the powertrain just about perfectly. The occasional tremor can disturb the peace at motorway speeds, a situation probably not helped by 21-inch wheels on Exclusive Premium spec, though otherwise it’s a model of composure.
Indeed the whole car is very good in a pleasingly unassuming fashion. Because it’s not pitched as a hypermiling eco special, the 450d gets proper tyres to the benefit of ride and grip; because it’s not attempting to blend a huge amount of regen as well as friction braking, the pedal feel is acceptable; and because there’s not an AMG badge in sight, there isn’t the same compulsion to go looking for thrills in a five-metre long, two-tonne car. You can just get on with appreciating an executive estate done really well, with well-judged, easygoing control weights, ample purchase and a bottomless vat of performance. It’s not so competent as to be forgettable either; that impression of well-honed engineering lingers fondly in the memory. As does less than half a tank showing nearly 300 miles.
Obviously, one car isn’t going to change the trajectory of diesel’s fortunes. With the tax situation for business users as it is and the advances made in EVs, something like the E450d looks like a tough sell. Even more so when every single spec is more than £80k. An EV works now for a lot of folk, even those on the road a good amount, because range and charging have improved (assuming you're mostly on the motorway network) - and that's before even thinking about the financial benefit. Nevertheless, the E-Class is proof of just how good the old methods can be when time and effort is lavished on them. It feels so utterly unburstable, in finest Mercedes tradition, from the solidity of the trim to the towering performance.
If you want to take the family to European skiing holidays (or summer beach ones) without dealing with the airport, or if you have a lot of miles merely to cover in the UK in far flung places and don’t want to plan your journey around a plug socket, it’s hard to think of much better. An Alpina is keener to drive while being more overt, and what’s left then? If some of the electric cars have exposed Mercedes a tad, this big diesel E-Class shows the firm at its most persuasive. And there’s not going to be another one…
2025 MERCEDES BENZ E450D EXCLUSIVE PREMIUM PLUS
Engine: 2,989cc twin-turbo diesel, plus mild hybrid drive
Transmission: 9-speed auto, all-wheel drive
Power (hp): 367@4,000rpm (23hp mild-hybrid boost)
Torque (lb ft): 553@1,350-2,800rpm
0-62mph: 5.0 seconds
Top speed: 155mph
Weight: 2,140kg (in running order with driver)
MPG: 42.8-44.8
CO2: 165g/km
Price: £88,945 (E450d range starts at £79,280 for AMG Line Premium or Exclusive Premium saloon, then £86,280 for AMG Line Premium Plus or Exclusive Premium Plus. Estates are £81,530 for AMG Line Premium or Exclusive Line Premium, £88,530 for AMG Line Premium Plus)
Oh, the price?
Uhhhhhh........ maybe I'll hold on to my old 3.0TDi A6 Avant for another wee while yet!
But to qualify, makes sense as a used purchase once depreciation has taken its toll.
Then, I think values will stabilise as there’s so little supply of diesels these days but there’s still a niche of people that still appreciate their virtues.
And as it’s Euro 6, isn’t it as clean as anything else?
A pity BMW have more or less abandoned diesel (in the U.K.)
But to qualify, makes sense as a used purchase once depreciation has taken its toll.
Then, I think values will stabilise as there’s so little supply of diesels these days but there’s still a niche of people that still appreciate their virtues.
And as it’s Euro 6, isn’t it as clean as anything else?
A pity BMW have more or less abandoned diesel (in the U.K.)
unfortunately yes although I think it will be a while before I'm spending a hundred grand on the family estate, so the used car market it is (and probably always will be) But to qualify, makes sense as a used purchase once depreciation has taken its toll.
Then, I think values will stabilise as there’s so little supply of diesels these days but there’s still a niche of people that still appreciate their virtues.
And as it’s Euro 6, isn’t it as clean as anything else?
A pity BMW have more or less abandoned diesel (in the U.K.)
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