{"id":67736,"date":"2025-08-09T04:18:07","date_gmt":"2025-08-09T08:18:07","guid":{"rendered":"https:\/\/www.globalvillagespace.com\/tech\/the-last-stand-of-the-straight-six-diesel-why-these-luxury-powerhouses-still-matter-in-2025\/"},"modified":"2025-08-09T04:18:07","modified_gmt":"2025-08-09T08:18:07","slug":"the-last-stand-of-the-straight-six-diesel-why-these-luxury-powerhouses-still-matter-in-2025","status":"publish","type":"post","link":"https:\/\/www.globalvillagespace.com\/tech\/the-last-stand-of-the-straight-six-diesel-why-these-luxury-powerhouses-still-matter-in-2025\/","title":{"rendered":"The Last Stand of the Straight Six Diesel Why These Luxury Powerhouses Still Matter in 2025"},"content":{"rendered":"

Are Straight-Six Diesels Still Worth It in 2025?<\/p>\n

If you\u2019ve ever found yourself daydreaming about the golden era of premium diesels, you\u2019re not alone. There was a time when a lusty, turbocharged straight-six diesel was the go-to choice for anyone who wanted serious pace and long-legged efficiency. But fast-forward to 2025, and these engines are rapidly becoming unicorns\u2014rare, desirable, and on the brink of extinction. So, is it still worth hunting one down? Let\u2019s dive in.<\/p>\n

Why Did Premium Diesels Become So Popular in the First Place?<\/p>\n

It\u2019s easy to forget just how dominant diesel engines once were in the premium car world. Back in the early 2000s, even Formula 1 prodigies like Jenson Button were caught pushing the limits in diesel-powered BMWs. The appeal was simple: torque-rich performance, impressive fuel economy, and a sense of effortless cruising that petrol engines struggled to match.<\/p>\n

Diesel\u2019s rise wasn\u2019t just about road cars, either. Audi\u2019s relentless success at Le Mans with their TDI engines cemented diesel\u2019s reputation for durability and power. By the end of the decade, diesel was the default choice for many luxury buyers\u2014whether you were after a compact executive saloon or a V12-powered flagship.<\/p>\n

But then, the landscape shifted. Emissions scandals, tightening regulations, and the rapid advancement of hybrid and electric tech started to erode diesel\u2019s dominance. Suddenly, what was once a no-brainer became a question mark.<\/p>\n

What\u2019s Left for Diesel Enthusiasts in 2025?<\/p>\n

Today, finding a premium straight-six diesel feels a bit like searching for buried treasure. BMW, once a stalwart of the genre, is quietly phasing out diesel from its non-SUV lineup. Audi\u2019s range has shrunk to a handful of four-cylinder TDIs and the occasional V6. Even the mighty Volkswagen Group, with all its engineering prowess, has dialed back its diesel ambitions.<\/p>\n

But there are still a few gems left\u2014each with its own unique flavor. For this deep dive, let\u2019s focus on three standout contenders: the Alpina D4 S Gran Coup\u00e9, the Range Rover Sport D350, and the Mercedes-Benz E450d Estate. All three pack straight-six, twin-turbo diesel engines with mild hybrid assistance, all-wheel drive, and enough power to make you question whether diesel\u2019s time is really up.<\/p>\n

How Does the Alpina D4 S Stand Out from the Crowd?<\/p>\n

Climbing into the Alpina D4 S feels like slipping into something rare and special. Alpina, soon to be fully absorbed into BMW, has always been about understated luxury and surprising performance. The D4 S is no exception.<\/p>\n

Under the hood, you\u2019ll find the B57 straight-six\u2014an engine that\u2019s been quietly evolving since 2015. Alpina\u2019s tweaks give it a bit more punch than the now-defunct BMW M440d, and the result is a car that\u2019s both quick (0-62mph in around five seconds) and genuinely opulent. The ride is plush, the interior is beautifully finished, and there\u2019s a sense of occasion every time you drive it.<\/p>\n

What really sets the Alpina apart is its balance. It doesn\u2019t beg you to wring it out at every opportunity. Instead, it encourages a more relaxed, confident approach\u2014one where you savor the torque and the effortless way it covers ground. The extended shift paddles are a tactile delight, and the low-end diesel rumble is deeply satisfying.<\/p>\n

But there\u2019s a catch: production ends in December 2025, and order books close by July. If you want one, you\u2019ll need to move fast.<\/p>\n

Is the Range Rover Sport D350 Still the King of Luxury SUVs?<\/p>\n

Switching from the Alpina to the Range Rover Sport is a study in contrasts. The Sport is big\u2014really big\u2014and it wears its luxury credentials on its sleeve. The D350 model, with its Ingenium straight-six diesel, is the most potent diesel option in the lineup.<\/p>\n

On paper, the Range Rover doesn\u2019t quite match the Alpina for power-to-weight ratio, but in the real world, it\u2019s more than quick enough. The engine feels robust, and the augmented soundtrack adds a bit of drama when you\u2019re in the mood. Dynamic mode lets you play with the paddle shifters and even loosen the stability control\u2014a rarity in today\u2019s SUV market.<\/p>\n

However, the Sport\u2019s sheer size can be a double-edged sword. On narrow country roads, it feels every inch of its width, and the reliance on touchscreen controls for drive modes can be distracting. The days of big, glove-friendly buttons are gone, replaced by sleek digital interfaces.<\/p>\n

Despite these quirks, the Range Rover\u2019s ability to isolate you from the outside world is unmatched. The ride is supple, the steering is carefully tuned, and the cabin is a sanctuary. It\u2019s no wonder that, according to recent JLR data, 44% of Range Rover Sport buyers still opt for diesel\u2014compared to just 7% who choose pure petrol.<\/p>\n

How Does the Mercedes-Benz E450d Estate Compare?<\/p>\n

If the Alpina is about rarity and the Range Rover about presence, the Mercedes-Benz E450d Estate is all about quietly getting everything right. From the moment you settle into the driver\u2019s seat, surrounded by a panoramic display and high-quality materials, it\u2019s clear this is a car designed for those who appreciate the finer details.<\/p>\n

The E450d\u2019s OM656 straight-six diesel is a marvel of modern engineering. It delivers a mountain of torque from just over 1,000rpm, making the car feel brisk and responsive despite its size. The gearbox is silky-smooth, and the air suspension soaks up bumps with ease.<\/p>\n

What\u2019s impressive is how the E450d manages to blend performance, comfort, and practicality without any obvious compromises. It\u2019s not trying to be a performance car, but it\u2019s genuinely rewarding to drive\u2014especially on challenging British roads. The four-wheel drive system is playful yet secure, and the cabin is a haven of tranquility, complete with subtle luxury touches like perfume-dispensing air vents and knurled metal controls.<\/p>\n

Mercedes has been coy about the future of diesel in its lineup, but for now, the E450d stands as a testament to what a well-executed diesel can offer.<\/p>\n

Are Straight-Six Diesels a Dying Breed\u2014And Should You Care?<\/p>\n

The numbers don\u2019t lie: diesel\u2019s share of the new car market has plummeted in recent years. According to the European Automobile Manufacturers Association, diesel accounted for just 16.4% of new car registrations in the EU in 2023, down from over 50% a decade earlier. Hybrid and electric vehicles are rapidly filling the gap, and stricter emissions standards are making it harder for diesels to compete.<\/p>\n

But here\u2019s the thing\u2014if you value long-distance comfort, effortless torque, and real-world efficiency, a straight-six diesel still makes a compelling case. These engines are smooth, powerful, and surprisingly frugal. They\u2019re also some of the last of their kind, which adds a certain allure for enthusiasts and collectors alike.<\/p>\n

If you\u2019re considering one, don\u2019t wait too long. Production windows are closing, and the shift to electrification is only accelerating. For those who appreciate what these engines represent, now is the time to act.<\/p>\n

The Takeaway: The Last Great Diesels Are Here\u2014But Not for Long<\/p>\n

If you\u2019ve ever been tempted by the idea of a premium straight-six diesel, 2025 might be your last real chance to experience one new. The Alpina D4 S is a hidden gem, the Range Rover Sport D350 is a masterclass in luxury, and the Mercedes E450d Estate is quietly brilliant in every way that matters.<\/p>\n

Will diesels ever reclaim their former glory? Probably not. But for those who know what makes these engines special, the current crop is a fitting swan song. Just remember\u2014if you do decide to take the plunge, maybe keep your right foot in check on those French motorways.<\/p>\n","protected":false},"excerpt":{"rendered":"

\"straight<\/a><\/p>\n

\n These fine straight-six diesels make a strong case for buying an oilburner in 2025<\/p><\/blockquote>\n

Lusty premium turbo diesels were once the order of the day, but now they\u2019re a dying breed<\/p>\n

\n

May 2025 marks a slightly unorthodox anniversary: that of a 20-year-old Jenson Button being caught speeding on his way to Monaco, clocking more than 140mph on a French motorway in a BMW<\/a> 330d.<\/p>\n

\u2018Prodigy racer enjoys speed\u2019 would normally rank no higher than \u2018dog bites man\u2019 as headline fodder, but the fact he invoked the blues and twos of the gendarmerie in a diesel was too much for the papers to resist back in 2000.\u00a0<\/p>\n

The car was owned by Williams-BMW, and it\u2019s easy to imagine them gleefully reimbursing his \u00a3500 fine for the publicity garnered. The market for premium diesel cars swelled from there, primarily due to engineering nous within the industry.<\/p>\n

But there\u2019s clearly something delicious about the possible butterfly effect of a future Formula 1<\/a> world champion getting excitable in an oil-burner on an empty autoroute.<\/p>\n

By the end of the 2000s, diesel had become the de facto choice for most premium car buyers. Its might was proved annually in endurance racing, with Audi\u2019s<\/a> trophy cabinet needing reinforcement after relentless TDI victories around Le Mans.<\/p>\n

Across the decade the brand\u2019s road-going diesel range spanned from lowly three-pots to V12s, yet the firm now offers little beyond four-cylinder TDIs in its medium cars and a V6 for the brave souls spending big cash on an A8<\/a>, Q7<\/a> or Q8<\/a>. It\u2019s almost as if the wider Volkswagen<\/a> Group has something of a chequered history with diesel power\u2026<\/p>\n

For all the inexorable rise of diesel before its eponymous scandal, its dwindling appeal since 2015 has felt like more of a slow decline. Hybrid<\/a> and electric cars<\/a> have gradually welcomed the fuel\u2019s former customers, while pure petrol power has amped up its efficiency credentials.<\/p>\n

\"\"<\/p>\n

Drawing together three diesel heroes for this test \u2013 cars with a sizeable engine intrinsic to their ultimate appeal \u2013 uncovered vanishingly few candidates, and nowt with more than six cylinders.<\/p>\n

BMW appears to be phasing diesel out entirely, in fact, with only its SUVs<\/a> possessing diesel power on UK price lists. Your best bet of buying a sexier, sportier Bavarian car is a Buchloe-built Alpina<\/a> \u2013 but even then, you can only order until summer.<\/p>\n

Alpina is soon to be swallowed up by the BMW mothership, and talk of Maybach rivalry suggests rep-friendly cars like the D4 S Gran Coup\u00e9<\/a> we have here won\u2019t live on. It kicks off this group in terms of both size and price, although each of our trio possesses a straight-six, twin-turbo engine with a minor degree of electrified assistance.<\/p>\n

All send roughly 350bhp through an automatic \u2019box and all four wheels for a 0-62mph time in the region of five seconds. Only their inevitable span of weight \u2013 and the Alpina\u2019s convention-busting 168mph top speed \u2013 truly separates them in an on-paper comparison.<\/p>\n

It\u2019s the Alpina I hop in first, its exterior exuding glamour, its interior rich in luxury and its rarity tangible beside the more familiar shapes in our rural Derbyshire lay-by. The delicious past form of its maker is a not inconsiderable aside.\u00a0<\/p>\n

With little surprise the D4 S is an immediately lovely device and a really simple thing to get in and drive quickly and with confidence. Like all the best magic tricks, an Alpina\u2019s plush sleight of hand over torrid surfaces is a continual novelty.<\/p>\n

It doesn\u2019t lack the core handing appeal of its base BMW, but there\u2019s a cushioned layer here that requires the sunroof lip open \u2013 and Peak District birdsong flowing in \u2013 for me to remember the outside world exists at all.<\/p>\n

Most Alpina buyers make the price and power jump up to a petrol B3<\/a> or B4<\/a>, but those who go diesel are unearthing a hidden gem. Its B57 six has been in service since 2015, having had its debut in a BMW 7 Series<\/a> and since been produced in single-, twin- and almighty quad-turbo variants while also finding a home in the Ineos Grenadier<\/a>.<\/p>\n

\"\"<\/p>\n

Here it has enjoyed a welcome Alpina tickle to produce a mite more power than its BMW M440d base (which is no longer offered).<\/p>\n

Its chassis doesn\u2019t immediately corral you to pull the lowest gear, find the highest revs and start seeking the limits of its adhesion. I have no doubt the car will be capable if you chase such highs, but the smoothness of its delivery and shortness of its rev range inspire a calmer approach.<\/p>\n

Its lovely embossed, extended shift paddles feel great, mind, and relishing the valedictory feel of this whole affair, I\u2019m compelled to pull them even though the engine punches just as willingly and likely sips less fuel making its own decisions.<\/p>\n

An extended pull of the left paddle drops you to the lowest possible gear \u2013 a detail that always exposes a development team that relishes the act of driving.<\/p>\n

Higher revs induce more of the Alpina\u2019s synthesised soundtrack, yet it\u2019s the low-down, bassy diesel rumble that my ears enjoy most, and there\u2019s certainly enough torque to shorten shifts if you wish.<\/p>\n

Either way, this is a car that punches hard and in which you can build almighty pace with ever-faithful traction below you. \u201cIt\u2019s fast and frugal, effortless and opulent, enticing to travel in and engaging to drive,\u201d summarised Matt Saunders when he first reviewed this car.<\/p>\n

\"\"<\/p>\n

In short, it does everything. But not for much longer: production ends in December, meaning the order books close by July. Get in quick.<\/p>\n

Climbing into the Range Rover Sport<\/a> from the Alpina is only ever going to make the Firenze Red SUV feel its mass. The Sport is a sizeable car by any gauge and soars into six-figure pricing with little fuss.<\/p>\n

You can get a straight-six diesel hit for \u00a376,000 if you\u2019re happy with a 247bhp D250, but we\u2019ve gone for the most potent D350. This is a celebration, after all.<\/p>\n

With no knowledge of a larger Range Rover<\/a> you might fairly assume this was the real thing; it lifts its occupants far from the road both literally and metaphorically.<\/p>\n

Its Ingenium twin-turbocharged six is a good power source, if far from bewitching. Crucially, though, it feels a world away from relying on a strained four-cylinder latched to an e-motor, and while its power-to-weight ratio is comfortably the worst in this company, its ample performance makes for easily won progress.<\/p>\n

\"\"<\/p>\n

It\u2019s not the silent type at revs, although the almost eight-cylinder soundtrack of its augmentation feels welcome when you\u2019re in a suitably boisterous mood.<\/p>\n

Pull the paddle shifters in Dynamic mode and it gleefully butts up against the rev limiter, while the ability to loosen the reins on its stability control remains a privilege many of its SUV contemporaries have ceased to offer.\u00a0<\/p>\n

The ingredients are there for an involving drive, then, but the Sport feels unwaveringly large on roads such as this. It\u2019s an additional bind when its drive modes are toggled through the touchscreen.<\/p>\n

Indeed, everything is tucked within its curved display. You\u2019ll frequently nudge catseyes on thickly hedged lanes, so the last thing you need is a reason to glance away from the road ahead.<\/p>\n

I was half-expecting the Sport to be a bit of a paragon of sense, given older Range Rovers famously hosted big buttons receptive to farming gloves. But no more.<\/p>\n

The most likely result is you\u2019ll leave it in its default Comfort settings and bathe in the way it so insouciantly isolates you from your surroundings. At which point its charm is much more evident.<\/p>\n

\"\"<\/p>\n

\u201cCareful tuning of steering and supple but surprisingly sophisticated damping are the car\u2019s calling cards,\u201d we said in the Sport\u2019s full road test. And while those words still ring true, the car\u2019s colossal weight and width stymie its driver appeal on B- rather than A-roads.<\/p>\n

It never quite draws you in or inspires you to get more intimate with what it can do, which, knowing the breadth of its maker\u2019s ride and handling development, means missing out on some true expertise.<\/p>\n

Moreover, I\u2019m craving the older-school V8 diesels of Range Rovers past, whose extra muscle and timbre might just tease some life from this clearly capable chassis.<\/p>\n

It\u2019s a \u00a316k jump from this D350 to a V8 petrol P350, and when an SV paint finish can swallow half that deficit anyway, it\u2019s easy to see why one might indulge \u2013 although 44% of Range Rover Sport buyers still favour diesel against just 7% choosing pure petrol.<\/p>\n

JLR hasn\u2019t explicitly committed to a diesel future, saying only: \u201cThe flexibility of our world-leading powertrain technologies means we can continue to offer hybrid and ICE vehicles in our ranges as we begin to roll out full EV options.\u201d\u00a0<\/p>\n

Mercedes-Benz<\/a> is similarly ambiguous, saying it plans to \u201ccater to different customer needs, whether it\u2019s an all-electric drivetrain or an electrified combustion engine, until well into the 2030s\u201d.<\/p>\n

In the here and now, its E450d Estate <\/a>envelopes you like a hunkered-down C-Class after experiencing the chunky Sport. But there\u2019s no mistaking its brand positioning once ensconced inside, surrounded by the vast panoramic display of its three screens.<\/p>\n

It\u2019s not lacking tech, yet it doesn\u2019t feel overly burdened by it once you\u2019ve sussed its \u2018Hey Mercedes\u2019 functionality. Its speed limit bongs rank among the simplest to turn off anywhere.<\/p>\n

\"\"<\/p>\n

I don\u2019t remember any stock E-Class driving this well, and it feels far and away the briskest car in our group. Its superior torque figure is delivered from a mite over 1000rpm to swiftly cancel out its extra flab over the Alpina.<\/p>\n

The Mercedes pairs our trio\u2019s quietest engine with\u00a0the smoothest gearbox, one that allows you to flick the dinky metal paddles to change ratios yourself but which feels happiest when left alone. Its choices are smart ones even when you\u2019re making strong progress \u2013 which is something this car certainly inspires.\u00a0<\/p>\n

The E450d rides impeccably whichever mode its air suspension is in, while quick-witted but suave steering tucks the mass accurately into corners. Get back on the power and the rear axle assertively does the pushing on the way out of turns, its four-wheel drive system clearly open-minded about cornering attitude.<\/p>\n

You\u2019re soon carrying more speed than its demure outward appearance sets the stall for. On gnarly British roads like these, plenty of us would get most of the satisfaction we need from this car.\u00a0<\/p>\n

The groundswell of torque from its OM656 diesel engine \u2013 around in base form since 2017 and shared in this more powerful tune with the S-Class<\/a> \u2013 is likely a big factor.<\/p>\n

It\u2019s not an immediately enthralling engine, but it legitimises Merc\u2019s move away from V6 diesels in the mid-2010s by not sacrificing their class. It doesn\u2019t bother with the overt sound synthesis of today\u2019s foes, and while it\u2019s not trying to be a performance car<\/a>, it ends up being an utterly beguiling low-key driver\u2019s device.<\/p>\n

All the while, perfume pumps through the air vents amid an enchanting mix of tan leather and pinstriped wood, all your major touch points flourished with knurled metal edges.<\/p>\n

\"\"<\/p>\n

This E-Class is a car of bafflingly few compromises, one whose modus operandi feels thoroughly boosted by the large lungs and long stride of its diesel power.<\/p>\n

\u201cIt is entirely possible that once the current era of premium estate cars is put out to pasture, diesel power will be retired with them,\u201d reported our road test earlier this year. \u201cIf that is the case, the Mercedes E450d will stand as an exemplar of what made these cars such capable, effortless, characterful companions.\u201d<\/p>\n

Declaring a winner from this oddball group is hardly conclusive, but against all most rational criteria the E450d walks such a comparison.<\/p>\n

Rationality used to be the diesel byword, of course, but times have changed. If this truly is a last dance with the devil, the big Benz isn\u2019t the most covetable car here. That accolade belongs to a car whose days look numbered in numerous ways.<\/p>\n

It\u2019s the Alpina D4 S that I suggest you leap in and head for the continent. Just don\u2019t follow young Jenson\u2019s lead too closely.<\/p>\n

\"\"<\/p>\n<\/div>\n","protected":false},"author":1,"featured_media":67737,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"Default","format":"standard","meta":{"footnotes":""},"categories":[2,137],"tags":[],"class_list":["post-67736","post","type-post","status-publish","format-standard","has-post-thumbnail","category-featured","category-news"],"_links":{"self":[{"href":"https:\/\/www.globalvillagespace.com\/tech\/wp-json\/wp\/v2\/posts\/67736","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.globalvillagespace.com\/tech\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.globalvillagespace.com\/tech\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.globalvillagespace.com\/tech\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.globalvillagespace.com\/tech\/wp-json\/wp\/v2\/comments?post=67736"}],"version-history":[{"count":0,"href":"https:\/\/www.globalvillagespace.com\/tech\/wp-json\/wp\/v2\/posts\/67736\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.globalvillagespace.com\/tech\/wp-json\/wp\/v2\/media\/67737"}],"wp:attachment":[{"href":"https:\/\/www.globalvillagespace.com\/tech\/wp-json\/wp\/v2\/media?parent=67736"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.globalvillagespace.com\/tech\/wp-json\/wp\/v2\/categories?post=67736"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.globalvillagespace.com\/tech\/wp-json\/wp\/v2\/tags?post=67736"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}