Jeep Grand Cherokee

They came, they saw, they conquered. They went to award dinners and won things. That is pretty much the story of Jeep in the UK. A remarkable tale of success in which cynical British buyers with an in-built and largely justifiable distrust of all things American automotive, were won over by the Cherokee and the Grand Cherokee off-roaders.

Of course the image helped and the marketing. But the product was right too. Well priced, well equipped, just as good off-road as their Japanese and European rivals and much better than most on-road, the Cherokee and the Grand cleaned up on group tests. The only complaints concerned a lack of interior space, surprising for machines built to convey lardy US citizens about.

When the new Grand Cherokee arrived in the UK at Easter, it dutifully continued where the old one had left off, by beating a Land Rover Discovery and a Mercedes-Benz M-class in a TG group test. The only thing missing from its armoury was a diesel engine, which for a big off-roader is a problem.

That hole has just been filled with the arrival of a 3.1-litre, five-cylinder turbodiesel. It's built by the Italian company VM Motori and produces 138bhp. The horsepower might not sound that fantastic, nor the 0-60mph time of 13.5seconds, but the torque - the stuff that makes engines good for pulling things - is. With 283lb ft it produces almost as much torque as the 4.7-litre V8. It can tow loads up to 3,500kg, which is one big caravan or two heavily genetically modified pigs.

So what's the new Grand Cherokee turbodiesel like? Well, unless the boys at Chrysler fancy a few beers and a good night out, they really shouldn't buy tickets for the annual, Quiet Diesel Engine Awards dinner. Or, to bring this beating about the bush to an end, the new diesel engine is a bit noisy.

To be fair, the Grand Cherokees we sampled were pre-production units, although it's difficult to see how the racket is going to diminish. The problem doesn't manifest itself at cruising speeds, but floor the accelerator, and while the response of the automatic gearbox is fine, the response of the engine isn't. It's ear piercingly harsh.

OK, so if you buy a diesel off-roader you know you are going to have put up with a certain amount of noise. But where we may have gotten used to Jeep besting the opposition, this time it's way off the pace. Arch rival Land Rover does a much better job with its still newish five-cylinder turbodiesel the TD5, which is quieter, more refined and more economical. The similarly powerful but less torquey Discovery returns 30.1mpg on the official combined mpg cycle, the Grand Cherokee a rather poor 24.1mpg.

In between fuel stops it rides well and although the steering's a bit woolly it handles tidily on-road. It's also got kit to turn any Land Rover owner as green as their wellies; aircon, alloys, leather and CD player all come as standard. So does a three-year/60,000-mile warranty. All that's missing is peace and quiet.