Used 2015 Porsche Cayenne Diesel

Quick Summary
The 2015 Porsche Cayenne GTS and Turbo S fulfill slightly different roles in Porsche's lineup. The GTS nestles between the Cayenne S and the standard Turbo and poses as the driver's choice with upgrades to the suspension, a 440-horsepower 3.6-liter twin-turbo V6 and styling tweaks. By contrast, the Turbo S is the SUV for the Porsche driver who must tick every box. It boasts 570 hp from its 4.8-liter twin-turbo V8 and is fitted with almost every conceivable gadget from Porsche's gargantuan options list. Both vehicles are luxury SUVs that deliver segment-leading performance and amenities to go along with their sumptuous interiors.

What Is It?
The Cayenne is Porsche's midsize SUV and a rival to the BMW X5/X6, Range Rover Sport and Mercedes M-Class. While most of its competitors offer at least the option of seven seats, the Porsche is strictly for five passengers only. The new GTS and Turbo S models plug two very small gaps in the range.

The GTS badge designates models in Porsche's lineup that are targeted at hard-core enthusiasts. We're already fans of the Boxster, Cayenne and 911 GTS models, and the Cayenne seeks to build on their success with uprated suspension and styling, together with a 440-hp V6 engine. It sits between the 420-hp Cayenne S and the 520-hp Turbo in the Cayenne range. Its rivals include the BMW X5/X6 M and the Mercedes ML63 AMG. Base price of the GTS is $96,495.

By contrast, the Turbo S targets Porsche customers who must have the fastest and most lavish variant, whatever the cost. It features the most powerful engine in the lineup, a 570-hp twin-turbo V8 along with nearly every feature Porsche offers as standard. Base price for the Turbo S is $158,295.

What Do You Get With the New GTS and Turbo S Trim Levels?
The GTS is distinguished by a standard Sport Design package that includes more heavily stylized sills and wheel-arch moldings, together with 20-inch alloy wheels and a front end that mimics the Turbo. Also standard is a sports exhaust and Porsche's Active Suspension Management system (PASM), which lowers the ride height by nearly an inch for vehicles fitted with the standard steel suspension, or slightly less if you choose the optional air suspension. Porsche says its intent was to make the GTS the most agile of all the Cayenne models.

By contrast, the Turbo S's specification is for the gadget-fetishist. The chassis systems include Porsche Traction Management (PTM), Porsche Dynamic Chassis Control (PDCC) and Porsche Torque Vectoring Plus (PTV Plus), all of which are designed to ensure that this 4,927-pound SUV has a dynamic repertoire worthy of the Stuttgart crest.

LED headlights also come standard, while responsibility for stopping this behemoth falls on carbon-composite brakes boasting 10-piston front calipers. They are housed within 21-inch alloy wheels, which replicate those of the 911 Turbo. The only surprising omission from the standard specification is a sports exhaust system, which is an option.

How Do They Drive?
We must start with a major caveat. Our test-drive was done in the frozen wastes of Sweden. Even with the benefits of all-wheel drive and an armada of electronic systems, we were never able to deploy more than a modest percentage of the Porsche's ponies.

The GTS's 3.6-liter V6 develops 440 hp and 442 pound-feet of torque, enough power to deliver a 0-60-mph time of 4.9 seconds, says Porsche (or 4.8 seconds if you opt for the Sport Chrono package) and a top speed of 163 mph. We had no means of verifying these figures, but it's clear the GTS does not want for pace, and although some may miss the distinctive burble of the old V8, the sports exhaust system helps deliver a satisfying rasp.

At 4,651 pounds, the GTS weighs 285 pounds less than the Turbo S, and much of this saving is over the nose. It feels more agile and anxious to turn than the Turbo, and there is a delicacy to its approach that belies its size. The steering is beautifully weighted and the poise, balance and agility it showed on the ice bode well for more normal conditions.

We suspect that on dry, grippy asphalt the GTS will prove the driver's choice of the Cayenne line.

The Turbo S takes the sledgehammer approach to life. The 4.8-liter V8 employs two turbochargers mounted in the exhaust manifold to produce 570 hp and 590 lb-ft of torque. For such a large and sturdy-feeling vehicle, its performance is almost comedic. Porsche claims a 0-60-mph time of 3.8 seconds and a top speed of 176 mph. It may lack the subtlety or agility of the GTS, but for straight-line thrust, this is the SUV of choice.

How Do They Rate in Terms of Interior Comfort?
The smaller Porsche Macan compact SUV has earned its share of rave reviews but if you want to carry a few adults and their luggage, the Cayenne is still a more desirable proposition. It lacks the seven-seater appeal of its key rivals, but five occupants travel in considerable comfort, and the luggage bay can be extended from 23.7 to 62.9 cubic feet with the seats folded. Given its versatility, it's little surprise that the Cayenne is currently Porsche's best-selling model.

Porsche's build quality is superb, but in other ways, the Cayenne is starting to feel old. The fascia is a cacophony of similar buttons (in the Turbo S we counted close to a hundred) and it lacks the luxurious simplicity of the Range Rover Sport or even Volvo's forthcoming (and much cheaper) XC90. Expect Porsche to develop a more sophisticated touchscreen system for the next-generation Cayenne.

As you'd expect, the Turbo S cockpit comes wrapped in plenty of leather along with extra details like the Porsche emblem embossed on the head restraints of the outer seats. Carbon fiber has also been used to decorate the interior, even if its weight-saving properties are worth nothing in this application. There's no denying that the Turbo S's cabin is a pleasant place to be, but we'd question whether it really feels worthy of a $160K SUV. You never really escape the feeling that this is a tarted-up version of a cabin designed for a sub-$100,000 sticker price.

Indeed, it feels little better than the GTS cabin, which is distinguished by lashings of Alcantara on the seats, roof lining and doors. There are subtle GTS logos and a brushed aluminum detailing that to our eyes looks at least as convincing as the Turbo S's carbon fiber. No one sitting in the GTS will feel as if they're in a cut-price alternative.

What Are Its Closest Competitors?
The latest generation of the Land Rover Range Rover Sport moves ever closer to the Cayenne's natural territory. It has the added versatility of seven seats, and the forthcoming SVR model should have the performance to match the GTS and even threaten the Turbo.

The BMW X5 M goes head-to-head with the GTS quite competitively, and if you want to make more of a statement (for good or bad), the X6 M is also worth a look.

The Mercedes M-Class isn't as inherently sporting as the Porsche, but in AMG trim it has more firepower (518 hp) than the GTS.

Why Should You Consider This Car?
You need a midsize SUV but you really want a sports car. The Cayenne GTS is about as close to a perfect compromise as you're going to get in terms of all-around performance, while the Turbo S has the kind of straight-line power typically reserved for super sports cars.

Why Should You Think Twice About This Car?
Objectively, it's hard to make an argument that the Turbo S is worth almost three times as much as the entry-level, 300-hp Cayenne, which we'd argue has 75 percent of its ability. We also find the $60K premium over the GTS hard to justify.

Edmunds attended a manufacturer-sponsored event, to which selected members of the press were invited, to facilitate this report.