Fleet News

Mercedes-Benz GL420 CDI



You might not like Boris Johnson and his floppy blond lid – or his stammery public school persona and right wing attitude to life and Liverpudlians – but you cannot deny that he has the strength of character not to modify what he says or how he behaves.

And I’d wager you will need to be a Boris-esque character to be truly at peace driving around in a Mercedes-Benz GL, because this thing is a two-fingered salute at those who might decry SUVs. It is Big and Brash with two capital Bs.

Actually, sport utility vehicle doesn’t exactly describe the GL, because sporty it is not. Nothing this big can be sporty, except for the odd Tongan rugby star. It is truly huge, at more than five metres long and weighing in at nearly two and a half tones.

I’m over six foot tall and it’s not often a car is taller than me. But the GL is. In fact, I took it to France on the Eurostar train and it couldn’t go in the regular car carriages – it had to go in an oversize cabin with the caravans and lorries.

Not surprisingly, this vast chunk of metal doesn’t come cheap and at nearly £64,000 there are few SUVs that are more expensive.

So what do you get for the money? Up front, there is a 4.2-litre V8 diesel engine that produces 306bhp and a gargantuan 516lb-ft of torque, which means it actually has some decent performance.

Amazingly, it will go from 0-62mph in a little over seven seconds, which is no mean feat considering the weight it has to get moving.

And once you’ve got some momentum, it will happily blast along at whatever speed you fancy, all done in a quiet and relaxed fashion. In fact, such is the size and plushness of the cabin, you’d be forgiven for thinking you were ever moving at all.

Of course, there’s a penalty for this and that’s fuel consumption.

The combined figure is 23.9mpg, although we found this surprisingly easy to hit on a long trip involving lots of autoroutes. And the car was packed to the rafters too, with five chaps and all their kit.

In terms of interior space, there’s not as much as you might think, despite three rows of seats, in which the third row fold electrically into the boot floor. This last row takes up a lot of usable boot space, making it not much better than many five-seaters.

Up at the front, where you feel a little like the captain of an airliner, the cabin is almost exactly as you would find in its smaller ML brother, which means quality materials, lovely soft leather seats and a plethora of buttons – so much so that I was discovering new buttons at the end of a week’s loan.

Piloting the GL is an interesting experience in which your two best friends are the parking sensors front and rear, acting like little electronic tug boats directing you through the tightest of channels.

The 12-metre turning circle of the car means that you spend an awful lot of time reeling the steering wheel back and forth, but at least it is very well assisted and I suppose if you did hit something, at least you’d win.

But in the end you have to ask yourself: does anybody on Britain’s clogged roads need a car of this size?

It’s certainly a very impressive feat of engineering and the engine is wonderful. The fit and finish, too, is top class.

However, for the vast majority of people with this much money to spend, you’d have to have a very specific lifestyle to tick all the GL’s boxes.

Fact file

P11D value: £63,522
CO2 emissions (g/km): 307
BIK % of P11D in 2007: 35%
Graduated VED rate: £300
Insurance group: 20
Combined mpg: 23.1
CAP RV (3yr/60k): £27,550/43%
Monthly lease (3yr/60k): £1,136




  • Great engine
  • Seven seats
  • Luxury



  • Huge size
  • Running costs
  • Boot space



  • Audi Q7 4.2 TDI Quattro S line
  • VW Touareg 5.0 V10 TDI Altitude
  • Range Rover 3.6 TDV8 Vogue

  • P11D PRICE

    The Audi seems like something of a bargain in this comparison, coming in top-specification S line trim with a lusty V8 diesel engine and seven-seat capacity. The Mercedes-Benz follows in a similar vein but is far more expensive, costing £13,000 more.

    Q7: £50,640
    Touareg: £57,282
    Range Rover: £62,250
    GL420: £63,522



    We’re talking off-the-scale emissions here, with the result that deep pockets are needed to run one of these as a company car. A 40% taxpayer will pay £590 a month in benefit-in-kind tax on the Audi, £668 for the Volkswagen and £700 a month-plus for the other two.

    Q7: 294g/km/35%
    Touareg: 299g/km/35%
    GL420: 307g/km/35%
    Touareg: 333g/km/35%



    Cars like this need plenty of rubber and it is this aspect which makes up the majority of costs here. Around £1,400 separates first from last here, with the Range Rover comfortably the cheapest at 5.50 pence per mile, which equates to an SMR spend of around £3,300. The Volkswagen costs nearly eight pence per mile, coming in at just under £5,000.

    Range Rover: 5.50 (pence per mile) £3,300 (60,000 miles total)
    GL420: 6.96 £4,176
    Q7: 7.61 £4,566
    Touareg: 7.93 £4,758



    The Audi is the most economical here, although this is a relative term for these huge, heavy vehicles. The Q7 returns a claimed 25.5mpg on the combined cycle. Unsurprisingly, the 5.0-litre V10-engined Volkswagen is last, recording a claimed 22.1mpg.

    Q7: 17.39 (pence per mile) £10,434 (60,000 miles total)
    Range Rover: 17.67 £10,602
    GL420: 18.18 £10,908
    Touareg: 20.07 £12,042



    The Audi is the cheapest to buy and has the best residual value, with CAP predicting it will retain 45% of cost new after three years/60,000 miles. The Mercedes-Benz will retain 43%, the Range Rover 38% and the Volkswagen 34%, reflecting its less prestigious badge.

    Q7: 47.44 (pence per mile) £28,464 (60,000 miles total)
    GL420: 61.20 £36,720
    Touareg: 63.47 £38,082
    Range Rover: 65.66 £39,396



    With a (relatively) low front-end price, the best RV and most frugal diesel engine, the Audi romps to victory, undercutting the Mercedes-Benz in second place by 14 pence per mile.

    The Range Rover and Volkswagen are well off the pace.

    Q7: 72.44 (pence per mile) £43,464 (60,000 miles total)
    GL420: 86.34 £51,804
    Range Rover: 88.83 £53,298
    Touareg: 91.47 £54,882



    At this level, money is not necessarily the deciding factor and for many in this position a Range Rover is the only vehicle of choice thanks to its image, style and performance.

    However, the Audi Q7 is just as capable and is massively cheaper to buy and run. The Mercedes-Benz is a fantastically capable car but offers nothing that the Q7 cannot do better.


  • WINNER: Audi Q7 4.2 TDI Quattro S line

    CO2 emissions and fuel consumption data correct at time of writing. The latest figures are available in the Fleet News fuel cost calculator and the company car tax calculator.

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