Why The BMW ActiveHybrid X6 Might Be The Worst Car Of The 21st Century

There’s always a kernel of truth hidden inside every automaker stereotype. Toyotas run forever because they’re generally overbuilt, quality machines driven by people who keep up with regular maintenance. GM products run badly longer than most cars will run at all because they’re a perfect blend of ‘fix it in post’ American manufacturing processes and engineering designed to shrug off deferred maintenance. BMWs are often regarded as hot garbage because pushing the envelope rarely results in reliable product on the first go. Believe me when I say, no BMW has pushed the envelope harder and failed more miserably than the ActiveHybrid X6.

This particular model is where a whole bunch of first-generation technology combined into a smorgasbord of misery for anyone who dared to run one after the warranty period expired. We’re talking notorious components mashed together, preposterous repair bills, difficult-to-source parts, the whole nine yards. All in the vehicle that kickstarted the questionable coupe crossover trend.

Are there less pleasant cars on the road? Sure, but few combine expense, unreliability, and marketing cynicism in such a skin-crawling manner to make you think an automaker shouldn’t have got away with this. Let’s put it this way: The Ford EcoSport is worse in the context of a review, but all things considered, the ActiveHybrid X6 has a solid shot at the title of worst car of the 21st century. Yikes.

The Background

Before even getting to the oily bits, there’s the issue of the X6 itself. The traditional Bavarian breakfast of Weißwurst, a pretzel and beer must have been in full effect when Chris Bangle’s design team decided to throw a fastback roofline on the X5 midsize SUV. In doing so, BMW created something with the fuel economy of an SUV and the practicality of a coupe. A steaming indictment of human vanity that’s spawned countless imitators.

Separately, I like fastback rooflines and I like SUVs, but blending the two always seems to create something with the silhouette of a FILA dinostomper. Adding to the ugliness is the general disjointedness of the ActiveHybrid X6’s design. Without the plastic cladding of the X5 to reduce visual impact, there’s just so much metal between the X6’s greenhouse and the ground. The three-level stacked-grille front fascia hasn’t aged particularly brilliantly either. Unique to the ActiveHybrid X6 is a hood bulge that clashes with the full-length scallops in the hood in an undignified display of make-fit necessitated by the hybrid wiring under the hood. Not the most beautiful thing on the road, is it?

If you were a major automaker looking to green up an SUV with a hybrid powertrain, what sort of engine would you use? How about a bleeding-edge, catastrophically unreliable twin-turbo hot vee V8? That doesn’t sound ostentatious at all! Dubbed the N63B44O0, this lump of aluminum was the first-ever hot vee engine in a production car. Packaging the turbochargers inside the vee of the block is a great idea – it allows for a narrower engine and reduces turbo lag thanks to shorter exhaust runners. The compressed air from the turbos was then fed through water-to-air intercoolers and into the engine. Sounds fairly simple, right? Unfortunately, a first-of-its-kind V8 from a company with an iffy track record of making V8 engines was never really a brilliant idea, and customers found out the hard way.

A V8 From Hell

It turns out that a hot vee turbo setup generates a lot of heat. So much heat that the electric auxiliary coolant pump for the water-to-air intercoolers had to run for an eternity after the engine was switched off. It turns out that 12-volt batteries don’t really like that, nor do they like BMW’s idea to only charge the batteries when coasting. Needless to say, reports of 12-volt batteries requiring replacement at every oil change weren’t uncommon. Speaking of electrical components with short lifespans, how does ignition coil replacement at 45,000 miles sound? Pretty terrible, right? Mind you, ignition coils are downright cheap compared to the early N63’s failure-prone high-pressure direct fuel injectors. Each fuel injector currently retails for around $449 and the updated parts had to be coded to the car in banks. If one injector on each bank resign from their duties, it’s time for nearly $3,600 of injectors alone.

Also on the menu? Timing chains that would stretch, valve stem seals that would dry out and fail, and seriously rapid oil consumption. In 2014, this engine was subject to something BMW called a Customer Care Package – a recall where BMW tiptoed gingerly around the word ‘recall.’ It covered a truly bewildering array of equipment: possible replacement of the direct fuel injectors, mass airflow sensors, crankcase ventilation system lines, turbo intake seals, fuel pressure sensor, vacuum pump, and timing chain. However, not every customer was eligible for every replacement part in the care package. As a result, BMW dropped the price of a long block down to $3000 in 2018. Mercifully, newer variants of the N63 engine share fairly little in common with the first-edition problem child and seem to be perfectly reliable. Still, that doesn’t change the fact that this first-iteration hot-vee hot mess found its way under the hood of the ActiveHybrid X6.

Grounds And Gears

Further complicating this lump of Bavarian engineering is a truly bizarre choice of gearbox. See, the ActiveHybrid X6 was born from the Global Hybrid Cooperation project, a joint venture between General Motors, Daimler, Chrysler, and BMW that dates back to 2004. In short, the people who made the Chevrolet HHR, Mercedes-Benz B-Class, Jeep Commander, and Bangle-butt E65 7-Series all decided to design hybrid technology together. What could possibly go wrong? Only a little thing called the Great Recession. The Allison AHS-2 gearbox born out of the Global Hybrid Cooperation project worked fairly well at the early stages of its life and was a pretty novel technology that deserves a separate deep dive. It also has really poor parts support because the Global Hybrid Cooperation was dissolved in 2009. As such, the ActiveHybrid X6’s gearbox is both shared with a Chrysler Aspen Hybrid and no longer available new. Not encouraging stuff considering hybrid drivetrain problems were reported within the first two years of the ActiveHybrid X6 going on sale. If the controller on the gearbox goes bad, a remanufactured unit costing more than $9,600 is the only way forward, and that’s assuming you can even find one.

All of this might be worth it if the ActiveHybrid X6 was astonishingly economical or amazing to drive, but it simply isn’t. In EPA fuel economy testing, it managed a disappointing 17 MPG (13.8 L/100km) city, 19 MPG (12.4 L/100km) highway and 18 MPG (13 L/100km) combined. In period road tests, reviewers lamented the SUV’s unrefined inputs. Car and Driver said, “Both the brakes and the newly electric power steering are drained of feel. The binders are terribly grabby at low speeds, and the pedal sinks all the way to the floor in a panic stomp.” Not exactly Ultimate Driving Machine material, then. Daniel Pund at Edmunds said, “The 2010 BMW ActiveHybrid X6 represents more work for less meaningful results than most first marriages.” Harsh, but fair.

Is This The Worst Car Of The 21st Century?

Let’s recap. The BMW ActiveHybrid X6 is ugly, impractical, unreliable, hideously expensive to run and not particularly good to drive. When new, it was also priced in a bracket that attracted people who should’ve known better. I mean, this thing had a sticker price of $89,775 in 2010, that’s an obscene amount of money to pay for an experience like this.

What’s more, it wasn’t even the most efficient option on its platform when it was new. The 2011 BMW X5 35d ran on diesel and got substantially better fuel economy, all with lower running costs, fewer common failure points, and a proper SUV roofline. Sure, the ActiveHybrid X6 was quicker, but it wasn’t better, and considering the current state of hybrids in America, failing to match compression-ignition economy with a hybrid is certainly a fail.

(Photo credits: BMW)

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