BMW working on quad-turbo diesel for ‘750d’, could replace M50d unit

You’ve heard of the tri-turbo diesel, currently available in BMW’s X5 M50d and X6 M50d. Now we hear there might be a quad-turbo diesel on the way from the Bavarian manufacturer, set to debut in the new 7 Series.

BMW X5 M50d engine

Rumours are heating up on BMW specialist websites, specifically, BimmerToday. It’s understood the company is working on a new unit to replace the M50d tri-turbo for an upcoming 7 Series model dubbed the ‘750d xDrive’.

Official information is limited at this stage but it is believed the engine will be based on the current 3.0-litre inline six. From there, it’s unclear if BMW will go for four conventional exhaust-driven turbines or instead implement increasingly talked about electric turbo technology.

Either way, if all is correct, we could be looking at the first quad-turbo BMW production car ever and the first quad-turbo sedan ever. Bugatti, of course, uses four turbochargers on the Veyron supercar and were thinking about releasing a production version of the Galibier sedan using the same engine, or a twin-supercharged version. The project has since fizzed out, as far as we’re aware.

So, what about the numbers for the 750d? The current tri-turbo unit produces 280kW of power and an Earth-moving 740Nm of torque. For the new unit, outputs are said to by lifted up to around 300kW and 800Nm.

The new 7 Series uses a technology BMW calls Carbon Core, with carbon fibre reinforcements making up sections of the main pillars. Even so, you wouldn’t call the car a lightweight. With output figures like these though, an all-wheel drive ‘750d’ may hit 0-100km/h in under 4.0 seconds.

The new engine may eventually find its way into the M50d versions of the X5 and X6 SUVs. Let’s keep our fingers crossed.

Brett is the editor and founder of PerformanceDrive. He's obsessed with driving, having played with Matchbox cars until he was tall enough to drive a real one. After initially working as a mechanic, Brett earned a degree in journalism and entered media as an editorial assistant at Top Gear Australia magazine. He then worked at His dream is to live next door to the Nurburgring in Germany.