Originally published June 18th, 2015

If the idea of spending well over a hundred grand on a diesel powered uber-lux German sedan just to save a few hundred bucks in fuel sounds a bit tenuous, the 2015 Audi A8L TDI and 2015 BMW 740Ld xDrive go a long way (literally) in dispelling the notion that you’d only buy one of these oil-burning oligarchs for the fuel savings.

It turns out the torque-rich demeanor of the modern turbocharged diesel six-cylinder engine fits the executive saloon mission statement to a tee. It’s all about the “waft”, and boy, do these cars know from wafting. You will be saving plenty of fuel too.

As Mercedes-Benz does not offer a diesel version of its current S-Class in North America, we brought this BMW and Audi together for a diesel-lux face off.

This generation of the BMW 7 has been with us since 2009, and an all-new and lighter version arrives later this year. Still, BMW didn’t let that get in the way of offering diesel power for this 7’s final year here in North America. The 2015 BMW 740Ld xDrive starts at $101,600 (a modest $1,500 over the base 315-hp straight-six gas model) and sports a turbocharged 3.0L straight-six making 255 hp and 413 lb-ft from 1,500-3,000 rpm. It is mated to the ubiquitous ZF eight-speed auto.

The Audi A8 is a newer prospect, getting a major refresh for 2014. That year also saw the introduction of this TDI diesel variant that makes use of VW/Audi’s twin-turbo 3.0L diesel V6, here with 240 hp and 428 lb-ft. Like the BMW, the 2015 Audi A8L TDI is all-wheel drive, long wheelbase and uses the ZF eight-speed box. At $98,100 it undercuts the BMW but asks a $5,300 premium over its 333-hp supercharged V6 stablemate.

As is the way with premium German cars, the automakers offer myriad packages and standalone options that quickly escalate the bottom line to penthouse levels. Granted, the view is pretty nice from up here. In the case of the Audi, $38,350 in options bring the tally to $135,150. The BMW has $23,450 in extra goodies, and a sticker of $125,050.

The Outside

Stately. Conservative. Big. That just about wraps it up for this pair of Swabian behemoths that manage to make their 20-inch alloys look a tad on the puny side. The BMW is particularly understated in its dark grey, and it essentially went unnoticed during my week of driving. Which is no bad thing, as flying under the visual radar in a swift executive sedan could very well be considered a bonus. This is not to say the 740Ld is unattractive. It is cohesive and quietly handsome, showing fine proportions and gently flowing bodywork that marks it with no uncertain terms as BMW’s flagship sedan.

Conversely, the Audi garnered quite a few second glances, no doubt attributable to its daring visage with the monstrous grille and cool headlights. This imposing snout did an excellent job of parting the proletariat while I cruised the 400 series highways here in Ontario. You could probably wedge a Micra in that maw and not even notice. The rest of the Audi A8 TDI does not really match its face, but it is sharply chiseled, appropriately regal and benefits from some interesting LED taillights.

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