Mercedes-Benz S320 CDI review (2006-2009)

Model: Mercedes S320 CDI Limousine
Bodystyle: four-door saloon
Engine: 3.0-litre V6 turbodiesel
Transmission: seven-speed auto, rear-wheel drive

What is it?

This is the Mercedes S320 CDI Limousine, a lengthened version of the S-Class. Stretched by 130mm over the standard car, it provides genuine limo-like levels of space for heads of state, captains of industry, celebrities and the generally long-legged.We're being sensible and testing the entry-level diesel model, which is the only diesel available, although a 4.0 V8 CDI is available in Europe and would be the pick for those who want a more sprightly drive with decent fuel economy.

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Where does it fit?

The S-Class faces strong competition in the luxury car market. The BMW 7-Series, Audi A8, Jaguar XJ and even the Range Rover are all viable alternatives, with strong-but-frugal diesel engines and acres of space.At the other end of the S-Class range the Bentley Continental Flying Spur is close in price and pace to the S65 AMG, a £150,000 no-nonsense hot rod. Within the S-Class model line-up, the S320 CDI is the entry point, with prices starting from £55,885, or £59,885 if you want the stretched car, which is comparable to rivals.

Is it for you?

Well, the S-Class has long been touted as the best all-round car in the world. It's comfortable, good to drive, classy but also austere, roomy and, with the S320 CDI, reasonably inexpensive to run.If this doesn't sound like your sort of thing, the S-Class is most certainly not for you. It's also one of the more attractive cars in this market, with the Jaguar XJ's styling looking a bit too sporting these days and the BMW 7-Series unfinished. And despite Mercedes' sliding reputation for reliability and prestige, when you get into the S-Class you are instantly reassured through excellent materials that this is proper luxury motoring.

What does it do well?

In a word, waft. The huge 90-litre fuel tank will get you from one end of the country to the other without stopping, intelligent cruise control will do the accelerating and braking for you, and huge, soft leather seats and an expensive Harman Kardon surround sound stereo make this one of the finest ways to travel. Unless you can afford a Learjet.On the road, the S320 CDI moves swiftly when you need it to, the well-proven 3.0-litre V6 turbodiesel summoning 398 lb/ft of torque from 1,600rpm for ample overtaking muscle. The dash to 62mph takes 7.5 seconds putting it not too far behind the V6 petrol. The ride is cushioned on the standard air suspension and the diesel engine smooth and refined.

What doesn’t it do well?

Can we skip this section? This is an incredibly difficult car to fault. For many, it might be too bland and common, in which case there are plenty of rivals. What else? Well, the seven-speed gearbox isn't exactly perfect and you can feel it make changes, especially when you put your foot down.This Limo version is also huge, and can be a handful to thread through congested streets or to find a parking space long and wide enough for it. And, even though it's diesel, don't underestimate the running costs such as servicing, insurance and repairs.

What's it like to live with?

I could probably live in this car if I needed to. The boot is simply vast, with 560-litre of boot space, the rear seats are big enough for three well-fed fat cats, and sitting in the front is like plopping onto one of those Lazy Boy chairs, without the holes for your can of Stella and TV remote.Accessing the S-Class' major functions - radio, DVD, sat-nav and telephone - is taken care of via the Command system. Like the BMW's iDrive system it is controlled using a single wheel, only this system is more intuitive. The interior also has a clock that wouldn't look out of place on the wrist of an investment banker.

How green is it?

This is the greenest S-Class you can buy, but that doesn't necessarily make it green. If you tread carefully you will get 33.6mpg on the combined run and as much as 43.5mpg on a cruise, while carbon emissions of 223g/km put it just short of the maximum of 225g/km and at the same level as petrol-engined saloons like the Audi A6 3.2 V6.

Would we buy one?

Without a doubt, the Mercedes S320 CDI is a supremely talented machine and every successive model moves the game on to another level, leaving other manufacturers to play catch-up. Compared to some rivals like the Lexus LS and BMW 7, it is maybe too conservative for some tastes.But few cars can deliver you to your destination in such comfort, refinement and smoothness - and in the real world, this S320 CDI is better to drive and quicker than the other S-Class' in the range all bar the most lunatic ones with AMG badges.

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More pictures of the Mercedes S-Class form Live Search
Buy a used S-Class from £1,300
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