The Mercedes GL has been sorely due a face-lift particularly since its smaller sister car, the M-Class, got a new chassis and much more efficient engines in 2012.
There are just two versions of the latest GL the 350 CDI (driven here) and the barmy, 549bhp V8-powered 63 AMG.
The GL350 CDI has a 3.0-litre V6 diesel engine, which does average economy of 38mpg and emits 192g/km of CO2. These figures bring gains of 8mpg and 50g/km compared with the outgoing model.
What's the 2013 Mercedes GL350 CDI like inside?
Anyone who's driven a latest-generation Mercedes ML will feel right at home behind the wheel of the GL, which gets a similar-looking dashboard, including a clear central display for the standard Comand infotainment system and a smaller display between the instrument dials.
Other Mercedes quirks such as a single stalk for the wipers and indicators are present as usual. The front cabin has a nice blend of quality materials, including double-stitched leather for the top of the fascia.
The middle row of seats provide a reasonable amount of space for three six-footers, and even the rearmost seats are big enough to be used by grown-ups although they are best left to kids if the journey is long.
The third row of seats collapses electrically into the boot floor leaving on almost flat loadbay. With the second and third rows folded, boot capacity increases from the standard 680 litres to an impressive 2300 litres.
There's a lengthy list of standard luxuries, too, including 21-inch alloys, sunroof, automatic lights and wipers, climate control, electrically adjustable and heated front seats, front and rear parking sensors, keyless entry, a multi-function steering wheel and sat-nav.
What's the 2013 Mercedes GL350 CDI like to drive?
At more than 5.1 metres long and over 2.1 metres wide, the GL is a simply massive car, and is pushing the boundaries of what's practical to live with on British roads.
Even though it's been lightened by up to 90kg, it still weighs 2.5 tonnes, and you're always aware the engine is working hard to haul around all this mass.
Our test car came with an optional 'On- and Off-road package', which adds locking differentials and alters the standard air suspension's set-up to make the GL a serious off-roader.
It also adds a 'Sport' setting for the suspension, although ride quality leaves a lot to be desired even in the 'Comfort' setting. At low speeds it's firmer and more jittery than you'd expect, although does settle on the motorway.
Handling isn't flawless, either. The steering is too light, particularly around the straight ahead, and wholly uninvolving the rest of the time. The plethora of computer aids can also make you can feel a little detached from the driving experience.
Still, you're just as well insulated from the surroundings, because the rolling refinement is excellent; there's precious little noise coming from the engine and both wind roar and road rumble are well suppressed.
With a fuel tank range of around 800 miles, the GL350 CDI is also an accomplished continent-crosser.
Should you be determined to increase your cornering speeds on twisty roads, Mercedes also offers the GL with optional active anti-roll bars. They still allow plenty of body sway, but it's always well controlled and acceptable for a car of this size and nature.
Should I buy one?
The Mercedes GL doesn't have many obvious rivals. The new seven-seat Range Rover Sport and the Audi Q7 are its closest competitors, but the GL is bigger than both of these cars, and is also competitively priced given its lengthy kit list.
However, you really do need to value that extra space, because while the GL is a great seven-seater, it's not as good to drive as smaller rivals.
The choppy ride quality could be a deal-breaker for some, but if you're willing to live with the restrictions imposed by its size and want a seriously plush SUV that can seat seven in comfort, the GL could suit your purposes.
What Car? says...
Specification Mercedes GL350 CDI
Engine size 3.0-litre diesel
Price from 59,485
Torque 457lb ft
0-62mph 7.9 seconds
Top speed 137mph
Fuel economy 35.3mpg
By John McIlroy and Vicky Parrott