Why the diesel-powered BMW 520d still offers compelling benefits

Psychiatrist Elizabeth Kübler-Ross theorised grief's journey has five stages.

Let me share the idea that recent BMW designs seem to be received by critics and commentators in three stages.

First, one recoils at how ugly the creation is, wondering what the head stylists were thinking, longing for the days of sleeker, more shark-like aesthetic archetypes.

Look at the 7 Series and compare it to the svelte E38 for example — no contest.

Second, after seeing the car in the flesh comes the acceptance that, OK, perhaps it needs to be seen close and in the right light to fully appreciate the cohesion of things. That probably applies well to the new G60 5 Series.

The third stage happens when BMW makes its customary life-cycle improvement, somehow making things more ungainly, as with the recently updated 1 Series.

At this point you realise that by contrast, the pre-facelift version was less unappealing than you may have thought.

Maybe my BMW behavioural model is not as smart as it seemed when the thought crossed my mind, during a 3.30am start behind the wheel of the latest 520d.

At that hour the head is a little groggy, despite me having gone to bed at 5pm the afternoon before.

My mission in the Teutonic sedan was to see what sort of fuel consumption could be eked out in a jaunt down the N3 and back in 24 hours.

Those looks might be debatable, but you have to hand it to the 5 Series: it delivers on the hallmarks of the lineage. Refined, luxurious, but imbued with sharp reflexes and a plugged-in sense that rewards keen drivers.

When equipped with the firm's famed 2l turbocharged-diesel, you can enjoy the perks of torque-richness and a truly parsimonious nature.

The four-cylinder is surprisingly silky, attesting to how well BMW has honed oil-burner technology over numerous decades. This is nothing like your aunt's E46 320d from 2001.

A diesel is the only engine you can have for now in the 5 Series line-up. No petrol serves the range and your only other option is the all-electric i5, which costs upwards of R600,000 more than the R1,248,731 required by the 520d.

There were no extreme and ridiculous hypermiling practices deployed on this run: no drafting behind trucks, no depriving myself of climate control functionality or folding in the side mirrors.

I blasted the air-conditioner (and heater) to my heart's content and while my use of the accelerator was gently measured, judicious, speed was not pegged at an unrealistic sub-100km/h pace. I kept things at the national limit of 120km/h, where possible on the N3, with its varying restrictions and abundance of heavy commercial vehicles.

Power output is an OK 145kW but the 400Nm of torque is what matters, offering a responsive sense of twist, facilitating a fairly brisk claimed 0-100km/h time of 7.3 seconds. The car weighs a little more than 1,800kg so that acceleration figure is by no means terrible. Drive is to the rear wheels, transmission is handled by an eight-speed automatic unit.

BMW quotes an average consumption figure of 5.6l/100km.

About 300km into the journey, our readout showed 4.7l/100km. The instrument cluster also showed a wince-inducing -3°C in Harrismith.

I braved the cold to stretch my legs, drinking tea from a flask while enjoying a warm roti roll leftover from last night's dinner.

Open-road driving makes it easy to achieve lower figures and the downhill stretch of the N3 allows many coasting opportunities.

Taking it easy, enjoying the mile-munching abilities of the business class Bimmer, keeping the throttle steady and resisting foot-flat take-offs from the tolls, I arrived at my destination in Musgrave on 4.5l/100km.

The trip distance from my starting point in Roodepoort was 617km on the dot and I pulled in just after 10am.

Remarkably, after a few shorter stop-go trips in and around Durban, the consumption rose minimally. It was on 4.7l/100km by the time I departed at 4am the next morning.

Mindful of the inevitable increase in consumption on the uphill leg of the N3, I opted to play things cooler than I did on the inbound trek. Less overtaking and occasionally short-shifting via the steering-mounted shift paddles to keep the tachometer low.

The consumption rose as expected, ticking up to 4.9l/100km where it stayed until the last stretch. Pockets of congestion entering Johannesburg had an affect on pace.

By the time I got home, after a trip of nearly 1,400km, the average readout showed 5l/100km on the nose. Still quite brilliant.

Diesel is a dirty word in many markets, but passenger cars such as the 520d — seemingly a dying breed — prove the fuel source offers compelling benefits to buyers who prioritise frugality.

The oil-burning 5 Series delivers that with an admirable level of sophistication.