You have a choice of three engines in the UK – a V6 (224 hp) 3.0 litre diesel, a V8 (306 hp) 4.0 litre diesel or if you prefer a petrol engine, there is a V8 5.5 litre, developing 388 hp.
How It Drove - Performance
You have a choice of three engines in the UK – a V6 (224 hp) 3.0 litre diesel, a V8 (306 hp) 4.0 litre diesel or if you prefer a petrol engine, there is a V8 5.5 litre, developing 388 hp. All engines are mated to Mercedes’ own seven-speed 7G-TRONIC automatic gearbox, there isn’t a manual option available.
We chose to drive the Mercedes Benz GL 420 CDI which is fitted with a 4.0 litre V8 diesel engine and the nearest match to the Range Rover TDV8 diesel we had tested the previous week.
The GL-Class was the first in the Mercedes Benz model range to be fitted with the high performance V8 diesel engine. It produces 306 hp and a hefty 700 Nm worth of torque at 2200-2600 rpm. This compares to the Range Rover’s TDV8 Diesel’s 271 hp and 640 Nm of torque.
Only when the Mercedes Benz GL-Class starts up are you going to audibly know or care that you are driving a diesel, otherwise it is pretty much a hushed affair, even under load it only lets out a rewarding grunt.
The 7G-TRONIC automatic gearbox has impeccable manners offering seamless changes whatever the driving conditions. The direct select gear lever, mounted on the steering column, can take some getting used to, especially when shifting between 1st and reverse gears – it seems more logical at first to seek the lever in the conventional place on the floor, but you soon get used to it. Should you wish to be more enthusiastic and drive the Mercedes Benz GL-Class in ‘manual mode’ you can shift gears by using the buttons on the back of the steering wheel.
Both on paper and on the road the Mercedes Benz GL-Class is a much quicker car than the Range Rover (0-62 mph 9.2 seconds) with a quoted 0-62 mph time of 7.6 seconds, which is pretty quick for a car of these proportions and weight. Although, there is a noticeable delay before the Mercedes Benz GL 420 CDI propels you forward with a satisfying grunt as the turbo chargers spin up. The top speed is quoted as an academic 143 mph which is not that far behind the 5.5 litre petrol V8 (0-62mph 6.5 seconds and top speed of 149 mph).
Once the Mercedes Benz GL-Class gets going it is much quicker than the Range Rover and feels a much more planted car to drive, which is partially down to its better handling and superior dynamics. The permanent four-wheel system (4-ETS) is very adept at controlling the power when necessary, between the front and rear to help keep you on course.
Realistically, we achieved 19 mpg whilst touring and motorway cruising was circa 25 mpg, which is around 8 mpg less than the Range Rover TDV8.
How It Drove - Ride and Handling
As we stated earlier the previous week we had tested the Range Rover TDV8 Diesel which, despite its impeccable ride quality, some compromises have to be made for its handling. Where on the other hand, the Mercedes Benz GL-Class does not quite have the ride quality of the Range Rover, but it certainly has better handling. Our test car was fitted with 20” alloys, with 275/50 profile tyres (a £560 option), which certainly looked the part.
We were surprised at how sure-footed the Mercedes Benz GL-Class is even when trying to provoke it, the parameter speed sensitive power steering is very direct and responsive. Even on ‘B’ roads you can have some fun – although its gigantic proportions may cause you to pull in the reins a little prematurely but at 6’ 4” wide it is only 2” wider than Mercedes S-Class saloon and the same width as its baby brother the M-Class.
The Mercedes Benz GL-Class benefits from AirMATIC air suspension as standard which aids both comfort and directional stability. Adapting for variations in vehicle load to provide a self-levelling function, the system can also be set to raise or lower body height. It can even automatically lower the ride height by 15mm at speeds over 85 mph which has the effect of reducing drag and improving directional stability.
The AirMATIC air suspension also works in conjunction with the ADS Adaptive Damping System which constantly adjusts suspension damper characteristics depending on how the car is being driven, how it is loaded and road conditions. Compression and rebound settings can be adjusted at each wheel instantaneously. Data is sent from a variety of sources including a steering angle sensor, acceleration sensors, and the ESP system.
This amounts results in a ‘stiffer’ ride when the Mercedes Benz GL-Class is driven in a more spirited manner and a more ‘comfortable softer’ ride during more relaxed cruising, such as on the motorway. You can even choose to override the automatic programmes and select modes which prioritise either sportier handling or greater ride comfort.
Mercedes Benz GL-Class Road Test Data
|Model Reviewed||Mercedes Benz GL 420 CDI|
|Performance (manufacturers data)|
|0 - 62 mph||7.6 Seconds|
|Top Speed||143 mph|
|Transmission||7G-Tronic 7-Speed Automatic Gearbox|
|CO2 Emissions (NEDC Figures)||g/km|
|Economy (NEDC Figures)|
|Extra Urban||30.7 mpg|
|Euro NCAP Rating||TBA|
|Warranty||3 Years / Unlimited Mileage|
|Price (when tested on the 08/11/08)||£63,642.44|