If there’s one thing that the BMW 5 Series has become particularly adept at over the course of its nearly 50-year existence, it’s the ability to make the wider car world collectively sit up and pay attention.
Upon its arrival back in early 2017, the seventh-generation, G30 version of Munich’s venerable executive car wasted no time in catapulting itself to the top of the class, with its mixture of driver engagement, luxurious refinement and efficient performance helping it maintain a vice-like grip on that position since.
Now, in a bid to grow its advantage and stave off the heightened threat posed by updated offerings from Audi and Mercedes-Benz, the 5 Series has been facelifted. Cosmetically, it has been sharpened up with new light and grille designs, but the crucial changes here are an expansion of the plug-in hybrid range and the introduction of 48V mild-hybrid technology on all four- and six-cylinder engines.
That said, the bread-and-butter 520d was the one 5 Series variant to benefit from the addition of an integrated starter-generator set-up last year, and here we’re driving it in the UK in newly facelifted, Touring estate guise for the first time.
The 2.0-litre four-cylinder B47 diesel engine is effectively the same as it was when the G30 5 Series was launched some three years ago. It continues to make a modest 187bhp and 295lb ft, all of which is delivered to the rear wheels through an eight-speed automatic gearbox. However, its 48V architecture now provides an additional 11bhp of electrical assistance, which should aid responsiveness when you need to get your foot down.
Like all mild-hybrid systems, this allows the engine to switch off while coasting and can help to spur the diesel engine along when you’re driving at a relatively consistent rate of knots. All of this, unsurprisingly, has been implemented in the name of marginal efficiency gains, but the big pay-off is that the 520d is now RDE2- compliant, so it isn’t hit by the 4% benefit-in-kind tax diesel surcharge.
Still, to any savvy fleet manager or business buyer, a BIK rating of 32% won’t be quite as tempting as the circa-10% scores the latest generation of plug-in hybrids are able to achieve. But for those private buyers after a big, efficient family estate, there’s very little about the way the 520d drives that’s likely to disappoint.