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Family considers diesel for their next SUV

Guys: We are in the market for a luxury SUV as our family "sedan." My wife drives a 2003 Lincoln Aviator that she absolutely loves, but it's time to for an update (we'd buy another Aviator if Lincoln made them). We have three- and six-year-old kids that are into everything, and a 70-pound chocolate lab, so capacity and reliability are very important. We are considering (i) the Mercedes GL350 BlueTec; (ii) the Audi Q7 TDI; and, (iii) the Land Rover LR4. I like the idea of a diesel given the family's thrice-a-week trek to King City, but my wife is skeptical. - Simon in Toronto

Cato: A little diesel story for you. A friend of mine, David, went to a full-service filling station where the attendant mistakenly pumped gasoline into the tank of David's ML320 diesel. Disaster.

Here David is, a $1,400 service charge later. The dealership had to do a thorough engine cleaning, as well as repairs to the high-pressure fuel pump which relies on the lubricity of diesel fuel for its lubrication. Moral of the story: never, ever pump gasoline - a solvent, in fact - into a diesel.

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Vaughan: Cato, I drive a diesel, and have never run into that problem.

Cato: I bow to your brilliance - and the fact you're too cheap ever to use a full-service station.

My first point to Simon: If you want a diesel, think through all the implications, including service and maintenance issues.

Vaughan: If Simon and his family treat their diesel with even a smidgen of respect and thoughtfulness, they'll love it. Simon, it's got to be a diesel for you and that rules out the Land Rover.

Cato, both Audi and Merc do beautiful diesels. They're not cheap but when you're hanging out with the millionaires of King City who worries about a few thousand bucks.

Cato: Wrong again. First of all, King City is not festooned with millionaires.

Second, the Audi Q7 3.0 TDI, the diesel, starts at $59,800 - a thousand bucks less than the base LR4 ($59,990) and 10 Gs under the GL350 BlueTec ($70,500).

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One other thing: Audi and Mercedes say their diesels are "clean" and that's true to a point. Both are loaded up with exhaust treatment systems designed to scrub clean the nastiest of diesel emissions - from oxides of nitrogen to particulates. But if Simon really wants a "clean" SUV, he should think about the Toyota Highlander or the Lexus RX400h.

Vaughan: Don't give me your Clean Air speech. How many times have I heard you say, "Well if it's an SUV, a diesel makes perfect sense?"

I'm not a rocket scientist like you, Cato. All I know is that both the Mercedes BlueTec and the Audi TDI are legal in 50 states and 10 provinces.

It's true that some diesels got pulled from California for a while, but they are now clean enough to meet the ever-more-stringent standards. In fact, an Audi TDI won Green Car of the Year award a couple of years ago at the Los Angeles Auto Show.

Cato: Yes, in 2010. And the Volkswagen Jetta TDI diesel was Green Car of the Year in 2009. Both votes were about great fuel economy. Even the cleanest diesel is no cleaner than the average passenger car. The cleanest hybrid, however, is lights-out superior to any diesel for sale now and any passenger car, too.

Vaughan: The vehicles, Cato, the vehicles. I like the GL's design. Squared-off and tough looking. It's very comfortable and not top heavy or tippy, either.

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As for the Audi, it's a beauty, too. I've never been crazy about the big nose they stick on the front of them with that monster grille, but Audi interiors are about the best in the world.

Cato: I like the affordability of the Audi versus the Merc. I have some reliability concerns about Audi in general, but here I have to embrace my inner Vaughan and praise the Q7 pricing.

Vaughan: What I will not do is recommend a gas engine anything over a diesel.

Cato, diesels are smooth, powerful, quiet and deliver about 25 per cent better fuel economy. And up in King City you can set up a still in the woods and brew your own biodiesel like Willie Nelson does.

Cato: I can picture you with a banjo and a piece of straw in your teeth. Simon, my pick would be the Audi on price.

But just for argument's sake, try that Highlander hybrid; you might be surprised at what it can do and how cleanly it does it. And with it, you won't need to worry about filling station attendants pumping in the wrong fuel.


2011 Mercedes-Benz GL350 BlueTEC

2011 Audi Q7 3.0 TDI

2011 Toyota Highlander Hybrid Limited

Wheelbase (mm)




Length (mm)




Width (mm)




Height (mm)





3.0-litre V-6, turbodiesel

3.0-litre V-6, turbodiesel

3.5-litre V-6 and and electric system with two electric motors and battery back

Output (horsepower/torque)

210/400 lb-ft

225/406 lb-ft

288 hp combined output

Drive system

all-wheel drive

all-wheel drive

all-wheel drive


seven-speed automatic

eight-speed automatic

continuously variable (CVT)

Curb weight (kg)




Fuel economy (litres/100 km)

12.4 city/8.8 highway

12.3 city/7.4 highway

6.6 city/7.3 highway

Base price (MSRP)




Source: car manufacturers

Jeremy Cato and Michael Vaughan are co-hosts of Car/Business, which appears Fridays at 8 p.m. on Business News Network and Saturdays at 11:30 a.m. on CTV.

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