MT Auto Parts Blog | Expert Tips for BMW enthusiasts on BMW Parts, Accessories, Engines and More

Photo by Rana Singh on Unsplash The BMW B47 diesel is one of the more important engines in the current used BMW market. It powers more models than almost any other unit in BMW's lineup, from the entry-level 318d to the X5 30d. Most buyers know the B47 as 'the diesel that replaced the N47 and fixed the timing chain problem.' That's accurate as far as it goes, but there's more to the B47 story, and the B47TU (Technical Update) is a significant revision that many owners don't know they have. This guide covers which cars have the standard B47, which have the B47TU, what changed between them, what goes wrong on each, and whether the reliability improvements are as meaningful as BMW claims. B47 vs B47TU: What's the Difference? The original B47 (2014–2018) BMW introduced the B47 in 2014 as the direct replacement for the N47 diesel. The headline improvement was the timing chain, moved from the rear of the engine to the front, making it significantly cheaper and easi...

  Image: BMW B47C20B complete engine with just 50K miles for sale at MT Auto Parts for £3,199.99 The B47 is BMW's answer to one of its own mistakes. When the N47 diesel developed a reputation for catastrophic timing chain failures, chains snapping at the back of the engine, behind the flywheel, turning reliable diesel cars into very expensive paperweights, BMW went back to the drawing board. The B47 engine arrived in 2014. It moved the timing chain to the front of the engine, where it belongs. It improved fuel efficiency. It met Euro 6 emissions standards. And it built a reputation as one of the better modern diesel engines in its class. That reputation is mostly deserved. But the B47 is not without its own problems, and some of them are serious enough that anyone buying a used car with one fitted should know about them before handing over any money. This guide covers what actually goes wrong, when, and what it costs to fix. What the B47 Is and Where It's Fitted The B47 is a 2...