BMW’s Ridiculous Quad-Turbo Diesel Engine Was Too Weird to Live

Also, it couldn’t meet emissions requirements. That too.

byStef Schrader|
BMW News photo


One of the weirdest engines in the industry—BMW's quad-turbo, six-cylinder diesel B57S—is going out of production in September, reports BMW Blog. It made nearly 400 horsepower in some of BMW's upper-range diesel models outside of the U.S., including 7 Series, 5 Series, X5s, X6s and X7s, but at the end of the day, it was simply the wrong weird engine at the wrong budget-tightening time. 

The B57S engine has been in production since 2016 and unsurprisingly, it was the only quad-turbocharged diesel on sale today. It made its debut in the 750d and then rolled out into BMW's biggest cars from there. 

Yet 2016 was right after the Dieselgate emissions scandal blew up, which changed the public's—and regulators'—perception of diesels. A diesel was no longer a fuel-sipping option that could help a company's fuel efficiency stats. It was a liability after Dieselgate's fallout prompted the adoption of stricter emissions laws. 

Worse yet, BMW's complicated quad-turbo diesel was expensive to build and maintain. Everyone's belts further tightened during COVID-19, and nothing about the costly, complex B57S makes sense in a pandemic.


Yet we'll miss the B57S as enthusiasts, not only because it was a true weirdo, but because its performance was commendable. It pumped out 394 hp and a whopping 561 pound-feet of torque. The author of BMW Blog's farewell post, Gabriel Nica, said that the crazy diesel was his preferred engine for the X7. It launched the big, 4,985-pound BMW X5 M50d from 0 to 62 mph in just 5.2 seconds. 

It's the kind of engine Americans drooled over from afar. If anyone has one out there just laying around, I, for one, would love to shove it into something tiny and ill-advised with a clean Florida title. 

BMW will give this lovable weirdo a nice send-off with Final Edition models of the X5 M50d and X7 M50d for Eastern and Central European markets. These will come with several standard upgrades, including Laserlight headlamps, comfort seats, gesture controls, autonomous driving assistants and its "Crafted Clarity" Swarovski glass trim bits. "Final Edition" will be inscribed on the door sills, too.

RIP, you lovable weirdo. With electrified drivetrains taking diesel's place as automakers' go-to for an efficient, torque-happy and environmentally friendly option, it's less and less likely that someone will pull out a Hail Mary of under-hood weirdness on this scale. Maybe there will be a unique EV configuration that will catch our eye next. Please amuse us, drivetrain folks.

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