North American purists of the Porsche brand, those who broke into tears and sobbed when a sport utility vehicle and five-door hatchback joined their beloved automaker's lineup, are going to need to suck it up once again – diesel has arrived.
While Europeans have been embracing and enjoying the torque and fuel efficiency of oil-burning Porsches since 2009 ("embracing" is actually an understatement – about 50 percent of Cayenne sales are diesel-powered overseas), the all-new Cayenne Diesel is the automaker's first non-gasoline model in our market.
Porsche flew us up to Alaska, the least densely populated state in the country, to put its latest Cayenne model through the paces amidst the region's spectacular scenery. It was a calculated move, but brilliantly played. Most thirsty SUVs require the driver to check the fuel gauge on a regular basis, but the miserly Cayenne Diesel returns 30-plus miles per gallon on the open road. Instead of staring at a moving needle, our attention turned to the melting glaciers, massive jagged mountains and abundant wildlife – but more importantly, we enjoyed a full day's worth of spirited seat time on less than half a tank.
We have enjoyed a slew of gasoline-powered Cayenne models since the SUV's introduction in 2003. The diversity ranges from the entry-level Cayenne (300-horsepower, 3.6-liter VR6) to the powerful Cayenne Turbo (500-hp 4.8-liter V8). There is even a hybrid gasoline-electric model. Despite their differences and price points, all are performance oriented.
The new SUV boasts EPA numbers of 19 mpg city and 29 mpg highway.
In contrast, the arrival of the Cayenne Diesel, a second-generation E2 chassis fitted with a diesel engine, is a distinct change of direction – it is oriented towards efficiency. The new SUV boasts EPA numbers of 19 mpg city and 29 mpg highway. Not only do those figures cleanly blow away the standard VR6 model's fuel economy (its EPA ratings are 16 city/23 highway), but they knock the Cayenne Hybrid (20 city/24 highway) down to second place on the environmentally friendly green podium.
Under the hood of the Cayenne Diesel is a turbocharged 3.0-liter V6 (the engine should look familiar to Volkswagen and Audi SUV owners, as a variant of the powerplant is currently under the hood of the Touareg TDI and Q7 TDI). The Gen-II engine, unique to Porsche at the moment (Volkswagen and Audi will get it for 2013), is constructed with a vermicular graphite cast iron block and aluminum alloy cylinder heads for strength, durability and low weight. The powerplant features common rail direct injection and a variable-vane turbocharger for increased output and efficiency, and diesel exhaust fluid (DEF) injection to reduce emissions. With a compression ratio of 16.8:1 and a maximum engine speed of 4,600 rpm, Porsche quotes 240 horsepower from 3,500-4,000 rpm and 406 pound-feet of torque between 1,750-2,500 rpm.
The V6 is mated to an electronically controlled eight-speed automatic transmission (Porsche calls it Tiptronic S) sending power to all four wheels. The permanent all-wheel-drive system, shared with the Cayenne Hybrid, splits torque 60 percent to the rear and 40 percent to the front under most driving conditions. If one of the wheels loses grip, an automatically self-locking center differential will transmit engine torque to the axle with the most grip. Porsche Traction Management (PTM) will also enable variable distribution of engine power to the rear of the vehicle to enhance turn-in.
With a curb weight of 4,795 pounds, Porsche conservatively estimates it will accelerate to 60 mph in 7.2 seconds.
With a curb weight of 4,795 pounds, Porsche conservatively estimates that the Cayenne Diesel will accelerate to 60 mph in 7.2 seconds, with its top speed of 135 miles per hour reached in sixth gear (seventh and eighth are overdrive ratios). The SUV is rated to tow upwards of 7,700 pounds, when properly equipped, a figure that bests both the Mercedes-Benz M-Class and BMW X5.
The Cayenne Diesel mirrors the standard Cayenne in physical appearance (the only diesel badging is found on each front quarter panel) and it is configured and priced accordingly. The base price is $55,750 (plus a $975 destination charge), slightly higher than the standard model. Full power accessories, partial leather seats and 18-inch alloys are standard, but upgrading with just a few of our test vehicle's options, such as a navigation system ($3,675), air suspension and PASM ($3,980) or 21-inch Sport Edition wheels painted black ($6,505), will quickly drain the piggy bank.
In spite of its unique powerplant, we found that the 3.0-liter turbodiesel drove much like its gasoline counterpart (splendid news for those harboring 80's-era diesel fears).
Credit a lighter curb weight and lower gearing, as turbo lag felt nearly non-existent.
A twist of the left-mounted key fob initiated the starting sequence. Quick-heating glow plugs (necessary to start compression-induced diesel combustion) heated up to 1,800 F in less than two seconds and the engine fired up immediately. The exhaust note is nearly nonexistent. Rather deliberately, the engineers in Stuttgart have done an admirable job hiding the diesel powerplant's characteristic clatter. Lift the hood and it is evident, but it's almost imperceptible from within the cabin.
Unlike the Euro-spec first-generation Cayenne Diesel we previewed nearly three years ago, fitted with the Gen-I 3.0-liter V6 turbodiesel and a six-speed automatic, the new model moved smartly from a standstill. Credit a lighter curb weight and lower gearing, as turbo lag felt nearly nonexistent. The lower gears moved the SUV briskly around town, and the engine pulled effortlessly. Despite a curb weight 300 pounds heavier than its gasoline-powered V6 sibling, and 60 fewer horses, our seat-of-the-pants impression is that the oil-burning Cayenne Diesel is quicker and more spirited at the lower end of the speedometer (there is no denying the thrust provided by an additional 111 pound-feet of torque).