In a move that sounds less like German engineering and more like a soap opera plot twist, we might soon be staring down the barrel of BMW engines inside Mercedes-Benz cars. Yes, you read that correctly: the Bavarian roundel under the bonnet of the three-pointed star. Somewhere in Stuttgart, an engineer just choked on his pretzel.

According to a whisper from Manager Magazin, Mercedes is in talks with BMW to buy its four-cylinder engines from 2027 onward. The candidate? None other than BMW’s workhorse, the B48 — a 2.0-liter turbocharged four-pot that’s already busy powering half the BMW lineup, from Minis to the X5. Built in Steyr, Austria, the B48 is as versatile as a Swiss army knife: it’ll fit sideways, lengthways, and probably even upside down if you asked nicely. For Mercedes, that flexibility means it can slot the engine into everything from compact runabouts to mid-size plug-in hybrids.

Now, some of you might be wondering: doesn’t Mercedes already have a four-cylinder engine? Indeed, it does. The shiny new M252, currently humming away in the CLA, paired with a mild-hybrid system. But here’s the snag — it’s about as good at playing nice with plug-in hybrid tech as cats are with bath time. Worse still, it’s built in China, which makes it a tariff nightmare for US-bound models. Cue the BMW B48 swooping in like a knight in Bavarian armor, potentially backed by a shared US engine plant to dodge Uncle Sam’s import taxes.

And this is where things get deliciously ironic. Remember when Mercedes promised in 2021 that it would be all electric by 2030? Fast forward a few years, and that dream has gone the way of your old iPod. With EV demand cooling faster than a Weissbier in the Alps, Mercedes has admitted that internal combustion will live “well into the 2030s.” Translation: the petrol engine is going nowhere, and Stuttgart needs a partner to keep the flames alive.

Of course, BMW is no stranger to lending out its engines. Morgan, Ineos, Range Rover — all happily running on Bavarian lungs. Even Toyota’s Supra isn’t shy about admitting it’s basically a Z4 in cosplay. But Mercedes? This would be unprecedented. Two German luxury titans sharing the same beating heart? It’s like discovering that Coke bottles its soda at the Pepsi plant.

If this deal goes through, expect purists on both sides to clutch their AMG and M Division rosaries. Will a BMW-powered Mercedes still feel like a Mercedes? Or will it have just enough Bavarian DNA to develop an annoying habit of tail-happiness on roundabouts?

One thing’s for sure: in 2027, the Autobahn is going to get a lot more complicated.

Source: Manager Magazin via Autocar