Used Mercedes-Benz M-Class 4x4 1998 - 2006 review

The Mercedes M-Class was one of the earliest prestige 4x4s and is built with a separate chassis, like a Land Rover. The result is that it has a more equal blend of on- and off-road abilities than many of its later rivals. So, whereas the M-Class isn't as good as the likes of the BMW X5 and Volvo XC90 on-road, it can show them a thing or two away from the Tarmac.

This means that, if you spend a lot of time on the road, you'll be disappointed by its low-speed ride, obvious body roll and cumbersome handling. However, if you want a genuine off-roader, you may be willing to put up with its shortcomings. What there's no doubt about is that the M-Class has one of the most spacious cabins of any of its rivals. It's on a par with the X5 for passenger and luggage space, and much better than a contemporary Land Rover Discovery.

This version of the M-Class has been the subject of two recalls, the first affecting nearly 4000 cars built in 1997, and issued because the driver's seat belt could disengage accidentally. The second affected almost 30,000 cars built in the four years from April 1998, and concerned a possible loss of power steering fluid.

Perhaps the biggest worry for a potential M-Class buyer is the damning reports from owners: the M-Class finished in the bottom five overall in the 2005 JD Power customer satisfaction survey, a very poor result for a company such as Mercedes. The biggest problems were the suspension and brakes, but faulty seats were also reported.

However, figures from Warranty Direct in fact show that the M-Class owners make fewer claims than average, although the bills on those occasions can be rather high. In Warranty Direct's experience, the electrics are weakest point, responsible for more than a third of all claims.

If you just want to get into a 4x4 with a prestige badge, the M-Class makes a lot of sense financially. Because it's been on sale longer than the BMW X5 or Volvo XC90, the cheapest M-Classes are several thousand pounds less than the cheapest XC90s or X5s.

There's not much to choose between these three cars for running costs, though. Insurance groups for the M-Class are almost exactly the same as those for the X5, and no more than a group higher than the XC90's. Fuel economy and servicing costs look very similar, too. However, it's worth bearing in mind that a four-wheel-drive estate car such as the Audi A6 Avant Quattro will cost much less to run.

You can also expect high bills if you need unscheduled maintenance. Hourly labour rates and average repair bills for Mercedes are among the highest around, although the bills are no worse than those for Jeeps and Land Rovers.

M-Classes are now widely available, but avoid Mercedes dealers to find the keenest prices, especially on older models.

If you can, go for a face-lifted model from a 51-plate onwards. Although the car didn't drive much better after these tweaks, the improvements to the materials and layout in the cabin went a long way to answering the criticisms of the original model. With any age of car, the 2.7-litre diesel is the best engine to choose, and preferably with the automatic gearbox. As we've said, the car's chassis is not the greatest, but its limitations are least obvious with the less powerful engines.

The diesel also has other advantages, such as its better fuel economy and strong low-rev pulling power, which is great for towing. There's a wide range of petrol engines, too, with the less powerful versions the best. Avoid the ML500 and ML55 AMG, which are too dear, and much too fast for their own good.

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