Executives confirm Land Rover will shift to independent front and rear suspensions to counter competition from car-based sport wagons such as the Lexus RX 300 and Volvo Cross Country, vehicles that have softer rides than traditional truck-based off-roaders.
The exceptions will be the Defender and any vehicle custom-made for disaster-relief agencies.
Typically, the Defender is bought by farmers and used in muddy conditions. Relief agencies need the more durable solid-axle suspensions because their vehicles operate in countries with poor roads.
But for the Discovery and the high-end Range Rover, independent suspensions appear to be the answer for Land Rover. The Freelander already has an independent suspension.
"We will still build the vehicle based on the suspension," said Bob Dover, Land Rover CEO. "Whatever suspension we use, it has to be the best off-road suspension in the segment."
Control, towing capacityThe main strengths of solid-axle suspensions are towing capacity and the amount of wheel travel they allow.
In extremely rocky terrain, for instance, 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.
In contrast, an independent suspension has more limited vertical 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 delivered to all the wheels adequately, and the vehicle can get stuck.
The more delicate suspension pieces also cannot handle 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 from solid axles for several years, while under the ownership of BMW AG and as a member of Ford's Premier Automotive Group of luxury brands.
Wolfgang Reitzle, who has overseen the testing of several Land Rover suspension systems as Premier Automotive Group chairman and, previously, as BMW's product development chief, says it has been an article of faith among engineers that a true off-road vehicle must always use solid axles.
Although the 2002 Ford Explorer, Jeep Liberty and Toyota Land Cruiser use independent suspensions, North American-market sport-utilities typically ride on solid-axle systems because of their perceived ruggedness.
But numerous prototype suspensions tested "under incredible conditions" showed it is possible to use independent suspensions instead of solid axles, he said.
"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. You have limits on a comfortable ride with a beam axle."
Market realities also are forcing Land Rover to revise its strategy. Its European sales are off 7 percent through August, following a 6 percent drop in 2000 to 90,838 units.
Pushed by the marketThere's a similar pattern in North America. Land Rover sales fell 8.4 percent through September, following a 7.6 percent drop in 2000 to 27,148 units.
Gilly Filsner, business manager of Morpace International Ltd., a market research company in Woking, England, said the shift may turn off some potential Land Rover buyers but is a necessary one.
"To a purist, anything that has leather upholstery isn't a real Land Rover," he said. "But you can't be profitable appealing only to the purists."