If you want to know what's coming down the pike in German luxury cars, just watch Mercedes-Benz, BMW, and Audi.

Whenever one maker launches a new car, crossover, body style, engine type, or performance package...the others usually follow.

And so it is with BMW, which reportedly plans to launch a diesel-engined version of its flagship 7-series full-size luxury sedan for 2014.

The 7-Series got a mid-cycle upgrade for the upcoming 2013 model year, but according to Car and Driver, the diesel model will trail the refreshed lineup--meaning it'll show up in dealerships roughly a year from now.

The engine will likely be the same 3.0-liter turbodiesel now used in the X5, where it develops 265 horsepower and 425 lb-ft of torque.

To suit the large 7-Series and provide higher-end performance, it may be slightly retuned to deliver more power and torque. The report notes that a higher-performance version of the same engine offered in Europe produces 308 hp and 465 lb-ft of torque.

2013 BMW 7-Series

2013 BMW 7-Series

The new model, which Car and Driver says could be named either the 735d or 740d, lines up directly against the Mercedes-Benz S 350 BlueTEC diesel luxury sedan launched last fall under the three-pointed star.

That car offers 240 hp and a whopping 455 lb-ft of torque, which may be an incentive for BMW to fit the more powerful turbodiesel to beat those numbers.

Similarly, Audi plans to introduce a 3.0-liter V-6 diesel in its A8 flagship luxury sedan, also most likely for the 2014 model year.

While the big BMW diesel won't be with us for a  year or more, we'll be testing a 2012 Mercedes-Benz S 350 BlueTEC over the next week or so.

We'll likely cover about 1,500 miles, so we'll let you know what we think of this large, luxurious German highway yacht fitted with Rudolf Diesel's combustion-ignition contraption.


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