Occasionally a vehicle hits the market with a big reputation, but surely none has arrived in Australia with as much to live up to as the Holden Suburban.

Billed as "the largest 4WD wagon on the planet", this re-badged Chevrolet has been hyped beyond belief, building expectations to the sky. A TV commercial depicting a road-train pulling up to give way to a Suburban, despitre its silliness, has further heightened our awareness that this is one big mother of a 4WD.

Even so, nothing quite prepares you for seeing one in the metal for the first time.

It's not so much the width, which at 1948mm is only 48mm wider than a Landcruiser, but Suburban's length is something else again! The 100 Series `Cruiser, at 4.89m long, almost looks like a runt when parked alongside Suburban's 5575mm.

Yet it's strangely not that big a climb to get into it, where you find a leather-wrapped steering wheel that is elegantly styled and mercifully lacking the hideous thumb-rests and knobs inflicted on so many tillers in recent years.

Interior space is never going to be a problem in this nine-seater wagon, which boasts more than ample legroom in both front and rear seats, even the third row.

The driving seat displays what seems to be an American peculiarity (noted in Jeep Cherokee, for instance), of a backrest that dictates a laid-back position with stretched arms that some people obviously find comfortable. But after a few days, my spine was crying `enough!'.

Power adjustment of everything in the front seats (except the backrest), makes them quite easy to adjust in every other respect, but their greatest shortcoming is the actual shape. Big slabs of soft foam covered in leather, they lack any deliberate contouring for support, though this big wagon is unlikely to be thrown into corners with enthusiasm anyway.

One thing that disappointed above all else was the chorus of creaks`n'groans that issued forth on anything other than mirror-smooth blacktop. Squeaks from the leather trim of the LT test vehicle were mildly annoying, but a frequent groan-nn from the centre of the dashboard began to raise doubts - was this luxobarge perhaps not all we had been led to expect?

Another question along those lines was raised by the ride, which had been anticipated to be in the silky-smooth category. It just goes to show that a gargantuan wheelbase does not necessarily guarantee such things, because Suburban actually proved slightly skittish over harsh bumps, the tail frequently doing an unexpected little hop on its leaf springs.

The auto transmission, on the other hand, was invariably smooth, blurring its way almost imperceptibly between gears. The shift lever is on the right hand side of the steering column, which is no great problem though its action was a bit stiff. Interesting, as Holden says that Suburban is not converted but "built for right hand drive by General Motors".

There's no choice of power modes, fair enough as the 5.7 litre lump of V8 under the hood of the Suburban 1500 has more than enough grunt to cope, with 190kW of power at 4600rpm and 447Nm of torque at 2800rpm. Which only left us wondering even more what Suburban 2500's 6.5 litre V8 turbodiesel must be like, with its barely adequate 145kW but 583Nm of torque (now that's serious grunt!).

The petrol V8 can get three-and-a-bit tonnes of Suburban moving without embarrassment, and on the open road in overdrive at 110kmh the engine is just ticking over at 2,000rpm. However, we always felt a little uneasy at the thought of all this metal being pulled up by front discs and rear drum brakes.

There's an awful lot of power left for overtaking (several motorists - particularly in little commuter jobs - looked almost horrified as the leviathan wagon lumbered by them).

But it doesn't go past fuel bowsers quite so easily - we averaged 19.6L/100km (14.4mpg) during our test run, and that was with the right foot feeling nervous after the first fill ran to 23L (12mpg). Ah, so that's why it has a 159 litre fuel tank!

And I won't easily forget the thrill of parking Suburban for the first time. Shopping centre carparks are enough of a challenge, but for real fun try parallel parking - power steering is fine, but estimating the space available is frequently Mission Impossible.

After a week of driving it, we were left wondering what this monster's mission in life is.

Okay, it will tow a very big dinghy down to the boat ramp, with a crew of nine (and their gear) aboard if you like, or fold the seats down and you have a big (and plush) panel van. But it's doubtful whether a Suburban 4WD will ever be seen on the more challenging off-road tracks of outback Australia.