Driving Mercedes-Benz GL-Class (2006 – 2013)
Engines for the UK are a 224PS 3.0 litre V6 diesel, a 306PS 4.0 litre V8 diesel and a 388PS 5.5 litre V8 petrol. The 4.0 litre V8 diesel is a new engine. Other markets also get a new 340PS 4.7 litre V8 petrol, All feed their power to the 4MATIC four wheel drive system via Mercedes 7-speed 7GTRONIC automatic transmission, and all have AIRMATIC suspension that enables you to raise the height of the body in three stages according to the severity of terrain you are asking the car to tackle. Kerb weight is a substantial 2,430kg to 2,550kg, allowing a braked towing weight of 3,500kg.
We drove three versions, the 420 CDI, the 500 and the 320 CDI over a variety of roads, terrain and even rivers in Iceland.
It has the same 7GTRONIC shifter toggles behind the steering wheel as the ML and SLK. Forward gets a lower gear. Back gets a higher gear. You can do this in manual or automatic modes, selected by a button on the console, but manual locks it in whatever gear you have selected until you change. For off road use, the two dials of the same standard ‘Off Road Pro' system (optional on the ML) allow you to select suspension height, locked centre diff and locked rear diff. At maximum ground clearance of 307mm and with the rear diff locked you are restricted to 30kph.
This system works very well indeed. So well that an off-road route playing follow-my-leader down a river was like a walk in the park. The accelerator pedal allows you to adjust your speed very finely or keep to a constant speed, which is often best policy while fording rivers.
Despite being fitted with Dunlop Grandtrek AT2 M+S tyres, the car handled very decently indeed for a big 4x4 on the road. Communicative steering, MB's heavily sensored ‘Dynamic Handling System', and the 7GTRONIC shifter enabled it to be hustled along at serious speeds (we saw 200kph in the 500), or simply cruised at a comfortable 120-130.
Though obviously the new 420 CDI is the engine of choice, the 320 CDI does the job more than adequately and doesn't ever feel underpowered in the manner of the 2.7TDV6 in the Discovery 3 or Range Rover. And you can justify it to Ken Livingston on the grounds it's a bus, capable of carrying 7 people comfortably, while delivering far lower emissions and much better fuel economy per person than a 40 seater bus containing 7. Despite the GL's bulk I preferred it to drive both on and off road to the ML.
Later I had a chance to get re-acquainted with RHD versions on UK roads and off them on a severe off-road course.
Only the GL420 CDI and GL500 were available on this occasion, and on UK roads there's not much difference between them in performance terms. Surprisingly, the 500 is slightly more fussy, needing to change gear more frequently to sustain the same sort of pace. The size is no impediment, as they seem to shrink around the driver and corner very nimbly. I preferred the driving experience to the R Class, though it has to be added that the R Class I drove was only a 320 CDI.
Off-road we had ample opportunity to try all modes of the Off-Road Pro system, employing the highest suspension setting, low range gears, centre and rear diff locks and manual gearchange as appropriate. It took everything the course could throw at it, seemingly with distain. And the cars we used were the same GLs we drove to and from the venue, all on Pirelli Scorpion M+S road tyres that both plugged through the mud and were pleasantly quiet on the motorway.
It may be huge, but the GL is currently the biggest and best SUV on the UK market and the only one capable of carrying seven for long distances in comfort. It pips even the Discovery 3 at that job.