2014 Audi Q5 TDI, Catskill Mountains, Oct 2013
You read a lot about hybrids and electric cars these days, but fuel-efficient diesel engines will be coming in certain classes of cars this year and in the future.
The most recent crop of diesel launches has been in the crossover utility vehicle class, of which we've now driven three different models.
2013 Mercedes-Benz GLK 250 BlueTEC 4matic, Catskill Mountains, NY, Sep 2013
The 2013 Mercedes-Benz GLK 250 BlueTEC hit the market about a year ago, using a four-cylinder 2.0-liter turbodiesel in place of that compact crossover's usual gasoline V-6 engine.
Then, for this year, the 2014 Audi Q5 TDI added a powerful turbodiesel V-6 to its Q5 utility vehicle, also a compact crossover, producing a fast, fuel-efficient, and very pleasant update to a model that's now several years old.
That model has a 240-horsepower, 3.0-liter V-6 turbodiesel that puts out a prodigious 428 lb-ft of torque, paired to an eight-speed automatic transmission and Audi's quattro all-wheel drive system.
Finally, the eagerly-awaited diesel version of the 2014 Jeep Grand Cherokee hit the market, and we eagerly tested that larger and heavier SUV during this winter's snows.
It is powered by a 240-horsepower 3.0-liter V-6 turbodiesel that puts out 420 lb-ft of torque, the same one fitted in the 2014 Ram 1500 EcoDiesel full-size pickup truck.
All three vehicles are easy to use, start up almost immediately even in the coldest weather, and are only sometimes discernible as diesels.
2014 Jeep Grand Cherokee EcoDiesel, Catskill Mountains, NY, Jan 2014
From the outside, the familiar rattle is apparent, but all three luxury brands have done a great deal of work to keep diesel clatter out of the cabin.
And the fuel efficiencies of all three vehicles are pretty impressive.
Surprisingly, the best fuel economy didn't come from the vehicle with least powerful engine.
Instead, the Audi Q5 TDI returned 35.1 mpg despite its power and almost instantaneous acceleration.
Then came the Mercedes, which has the smallest and least powerful diesel--albeit in a fairly heavy compact utility vehicle--at 33.5 mpg.
Finally, the Jeep Grand Cherokee EcoDiesel--which drives like a larger vehicle and has supreme all-wheel-drive capabilities--gave us 27.4 mpg on our usual test route, which is roughly two-thirds highway and one-third city and suburban stop-and-go usage.
UPDATE: Earlier this year, we had a few days with a fourth diesel SUV, the 2014 Volkswagen Touareg TDI Sport with Navigation, with a bottom-line price of $51,945. It is powered by a 240-hp 3.0-liter turbocharged V-6 diesel powering all four wheels through an eight-speed automatic transmission.
Surprisingly, the Touareg TDI only averaged 22.7 mpg per its trip computer, on a 213-mile test route of about 40 percent city driving (including some time idling in parking lots) and 60 percent highway speeds while temperatures were in the 30s and 40s.