Land Rover is moving away from one of the vital components that have long made it the No. 1 off-road vehicle brand.
In a shift that will upset off-road purists, solid-axle suspensions no longer are essential on future Land Rovers.
Traditional sport-utilities are under attack from car-based sportwagons such as the Lexus RX 300 and Volvo Cross Country. As a result, many automakers are giving their truck-based SUVs softer rides and more compliant suspensions.
For example, Toyota redesigned its Land Cruiser with an independent front suspension for the North American market.
In the case of Land Rover, it will phase out truck-like solid-axle suspensions in favor of independent front and rear suspensions, executives have confirmed.
The exceptions will be the utilitarian Defender, and any vehicle custom-made for disaster-relief agencies.
Poor road networks
The Defender is typically bought by farmers who use vehicles in muddy conditions. Relief agencies need the more durable suspensions because their vehicles operate in countries with poor road networks.
But for models such as the Discovery and the high-end Range Rover, independent suspensions appear to be the way forward for Land Rover. The Freelander already has an independent suspension setup.
'We will still build the vehicle based on the suspension,' said Bob Dover, Land Rover chairman and CEO. 'Whatever suspension we have, it has to be the best off-road suspension in the segment.'
The main strengths of solid-axle suspensions are towing capacity and the amount of wheel travel they allow.
For instance, in rocky terrain, a pair of solid axles allows all four wheels to maintain ground contact and vehicle control. And because it is a single unit, there is more pulling strength.
An independent suspension has more limited wheel travel. In extreme conditions, one or two wheels can hang in the air, making for less off-road control. In such circumstances, power cannot be adequately delivered to the all wheels, and the vehicle can get stuck.
The more delicate suspension pieces also cannot handle very heavy loads. But independent suspensions offer a more refined on-road ride.
'With the Range Rover, we will have the best off-road vehicle, while also being good on-road,' Dover said. 'But it really depends on use and expectation. For customers who never take the vehicle off-road, how many could really tell what kind of suspension there is?'
Land Rover has studied moving away from solid axles for several years, both while under the ownership of BMW and now as a member of Ford's Premier Automotive Group of luxury brands.
Wolfgang Reitzle, now as Premier Automotive Group chairman and previously as BMW's boss at Rover, has overseen the testing of numerous suspension systems.
Early in the testing, Land Rover engineers were convinced that a true off-road vehicle must always use solid axles, Reitzle said.
But numerous prototype suspensions tested at Land Rover's off-road facilities at Gaydon, England, 'under incredible conditions' showed it was possible to use independent suspensions instead of solid axles.
'Having a solid axle might be for a workhorse like the Defender, where you have to pull heavy loads or you have an extreme use of the car,' Reitzle said.
'But on-road, an independent suspension runs much more stable. The beam-axle has bump-steer, where if one wheel hits a bump, it makes the car jump sideways somewhat. You have limits on a comfortable ride with a beam axle,' he added.
Previously with independent suspensions, a wheel hanging in mid-air meant loss of off-road traction. But Reitzle said modern slip-control and traction control systems can stop the airborne wheel from spinning electronically, allowing the grounded wheel to get grip.
Market realities are also forcing Land Rover to revise its strategy.
Land Rover European sales are off 7 percent through August, following a 6 percent drop in 2000 to 90,838 units.
There's a similar pattern in North America. Land Rover sales fell 7 percent through August, following a 7.6 percent drop in 2000 to 27,148 units.
Gilly Filsner, business manager of Morpace International Ltd. market research in Woking, England, said Land Rover's image alone is enough for most buyers, who never take their vehicles off-road.
'In theory, people in Europe who buy sport-utilities really need them, and are more concerned with off-road capability,' Filsner said. 'But increasingly, they are following the American consumers' desire of being up above things and thinking they are safe.
'To a purist, anything that has upholstery isn't a real Land Rover, but you can't be profitable appealing only to the purists.'