  2014 Mercedes-Benz ML350 BlueTEC & 2014 Porsche Cayenne Diesel. Click image to enlarge |
The Diesels
Mercedes-Benz ML 350 Bluetec and Porsche Cayenne Diesel
Of our esteemed group of luxury utes, only two were diesels. It’s probably not surprising that both were German, given that nation’s love for the frugal powertrain.
Priced about mid-pack, our two German oil-burners were stickered within one thousand dollars of each other.
But there the similarities end. Although the Mercedes-Benz ML 350 Bluetec and Porsche Cayenne Diesel are both beautifully engineered premium luxury utility vehicles, they each exhibit quite different characteristics.
At first glance, the eye is drawn quickly to the Porsche, with its raked roofline, sexy coupe-like front end and dynamic lines.
But there’s something reassuring about the quiet solidity of the Mercedes – the chiselled sheet metal in subtle charcoal grey, as respectable as a Frankfurt banker in a Hugo Boss suit. Obviously I wasn’t the only one who felt this way, as the ML tied with the Range Rover Sport for top marks in exterior design.
The Cayenne’s interior received high marks from the Autos.ca team. It features the same interior treatment found in most Porsches: the cockpit-dividing centre console featuring an orderly array of switchgear, machined aluminum trim, and plump stitched leather seats that fit the backside like they’ve been custom molded to it. Only the BMW X5 scored higher in this group for interior styling.
The ML’s interior ranked about mid-pack in this group. It’s a dark, rather sombre environment but like most offerings from this premium manufacturer, it’s well-crafted using first-rate materials. Seats are really comfortable, providing a more relaxed driving position than in the sporty, high-bolstering of the Porsche.
  2014 Mercedes-Benz ML350 BlueTEC & 2014 Porsche Cayenne Diesel dashboard. Click image to enlarge |
The ML scored the highest points in the group for ease of entry and positively voluminous second row. There was plenty of shoulder, leg and headroom for rear passengers. It also ranked highest in the group for ease of child-seat installation with its quickly accessible tether. The Cayenne, on the other hand, ranked worst in group for its cramped rear space and frustratingly fiddly kid’s seat installation process.
In this segment, a high level of luxurious features is expected – and for the most part the competitors don’t disappoint. All except one are so well appointed that they fall within decimal points of each other.
The exception is the Cayenne. Like most Porsches, it’s low on standard content, and any additional features come with a high price tag. It’s the only one of the bunch without a back-up camera – available as part of a $10,990 Premium Plus Package, along with Parking Assist and Lane Change systems that all the other test vehicles did have at this price point. This helped contribute to the Porsche’s low sightlines score.
The poor Cayenne also trailed the pack for cargo space, cargo flexibility and cabin storage, while the ML was mid-pack in all three.
   2014 Porsche Cayenne Diesel seating & trunk. Click image to enlarge |
The ML took the top marks for noise, vibration and harshness, its smooth performance and quiet ride gave it the most poised ride of the group.
It was also best in the group for both ease of driving and ride comfort.
Surprisingly – the Cayenne came in at the bottom for ride comfort – for me, the firm ride was a plus, but apparently the rest of the judges thought otherwise. However, it took the top marks for handling – given its Porsche DNA, this should be no surprise.
It was also just a fraction below the BMW X5, the winner for driving enjoyment, with the ML just another fraction below it.
   2014 Mercedes-Benz ML350 BlueTEC seating & trunk. Click image to enlarge |
Long gone are the days when diesels were notable for their harsh, clattering performance, lack of refinement and objectionable smell. Both the ML and the Cayenne scored well for their powertrains, with the Range Rover Sport taking the top marks for its powerful supercharged V6.
At $74,625, the ML was priced mid-pack, yet was voted “best value” of the bunch. For that price, it came with almost every conceivable safety and technology feature, including an adjustable ride height that raised the car for more off-road ground clearance.
The Cayenne was slightly more expensive at $75,415.
Despite some of its shortcomings in other categories, the Porsche was the hands-down winner for “cachet” – that subjective value of desirability that this German sports brand has in droves. It also scored the top mark for fuel economy, with one of our writers observing average fuel numbers in the mid-7 L/100 km range. The ML was right behind it, proving the excellent efficiency of these new clean diesel powerplants.
At the end of the day, the Mercedes took the top spot for overall winner – quiet, beautifully engineered and comfortable to drive, it would be the easiest of the bunch to live with. With highs and lows all over the score chart – the Cayenne ended up mid-pack overall.
2nd: Porsche Cayenne Diesel (4th overall)
1st: Mercedes-Benz ML 350 Bluetec (1st overall)
