Over 6ft tall and roughly the length and width of a cross-channel ferry, the Toyota Land Cruiser does not mess around. It is built to do the jobs that other cars tremble at. Mining, for instance. The Land Cruiser is the vehicle of choice in the mineshafts of, among other places, South Africa, mine-owners finding that its eager work-rate and durability make it a smarter choice for underground employment than, say, a secondhand Vauxhall Corsa.

The Land Cruiser also nonchalantly puts its hand up when there is polar exploration to be done. Given Antarctic wastes to cross at temperatures stooping to a parky minus 75 degrees celsius, the Japanese South Pole Observation Team wouldn't dream of packing their boots into the back of anything else.

Last week I took delivery of the new model, which replaces the Land Cruiser Colorado. Whether the car was named after the US state, or the state after the car, is thus a question which no longer need trouble us. Obviously, if you get given a brand new Land Cruiser to test with a 3-litre engine, you need to put it through its paces. Constructed the old way, with the body bolted on to a chassis - unlike today's namby-pamby, all-in-one, monocoque numbers - this is a car intended to take the worst that driving can throw at it, both on and off the road. Land Cruiser owners know that the shortest route between A and B is frequently across a crowded field. The fact that the running boards are mounted high enough to clear an only slightly crouching sheep is no coincidence.

I wanted to do something with my Land Cruiser that would test to the maximum its much-vaunted capacity to cope. After all, this is no Vanessa Come Lately sports utility vehicle: this is a car with half a century of fearless automotive history behind it. (It was the first model Toyota ever exported.)

I wanted to push the car's fabled engineering to the limits in the toughest contemporary setting I could imagine. I wanted to dare it to perform. I wanted to frighten us both and see who backed down first. So I used it to return a mattress to a branch of Habitat in Croydon.

Risky, I know. But what are you going to do? The lavishly carpeted and leather-lined interior might seem a little workshy, but the chunky front grille and steroidal bumpers appeared to demand action.

I should mention right now, before I get accused of recklessness, that it was only a single mattress. Clearly a double would have been a sterner test - though one the car was obviously on for, size-wise. I opened the back door, activated the one-hand-only "tumble-tilt" mechanism on the two rows of rear seats and slid in my single.

It got dwarfed in there. It looked like a solitary suitcase on the back of a lorry. At any rate, I reckon you could have got a double one in alongside it. The Land Cruiser comfortably seats eight. I am in a position to report additionally that it would comfortably sleep three.

It was journey time. I pulled myself aloft into the cab, steadied my nerves with a few deep breaths, checked the wing mirror, which is the size of a widescreen television, and pulled away. For something so large, and so diesel-powered, the Land Cruiser gathers speed with pleasing and also terrifying ease.

One's only question then is whether, like one of those trucks that travel the Outback, it will require a number of clear miles in which to come to a halt. Because a number of clear miles are not automatically available for that kind of thing in Tooting Bec.

In fact the brakes are miraculously efficient. And all of the car stops at the same time, which is nice. I was soon rounding Amen Corner and settling into my seat a little - unlike the mattress, which was rattling around in the back.

But at least my coffee was holding firm, held in place by an adjustable plastic clip within the cup-holder. That is the kind of thinking that can keep a car company ahead of the pack. And light was flooding through the panoramic windows and the noise of the engine was far away - almost as far away as the other traffic, going about its business somewhere down below.

Then, on a roundabout in Mitcham, somebody in a van pulls out in front of me and stops. And in that split second, it occurs to me that, although I am unlikely to be killed by the impact, I may suffocate under the mattress. But I jink the wheel right, then left, and the Land Cruiser responds like a cat and I am round this madman and through. We surf the speed bumps on Watneys Road, ease left off Purley Way and we are there.

A staggering performance. Yet in Britain, the Land Rover Discovery outsells the Land Cruiser by 10 to one. Why? The Discovery looks like a horsebox. For those tough jobs, I would prefer the prettier Land Cruiser every time.

Problems since? None whatsoever. When you return a mattress in a Land Cruiser, it stays returned.