Who's your Daddy?: How the world's most luxurious and expensive SUV was nurtured by three parents — and turned out to be so good - New Vehicles/2003 Range Rover

Automotive Industries, April, 2002 by Don Sherman

What's the secret to building a luxury SUV capable of crawling over the pretenders to the very top of the off-road hill without soiling its formal attire? In David Sneath's case, the answer is endurance. Sneath is the chief engineer of Land Rover's 2003 Range Rover and the man who suffered:

* Consternation when Land Rover became part of the BMW Group in 1994;

* Rejection when BMW's product guru Wolfgang Reitzle vetoed his plan to upgrade the existing second-generation Range Rover in 1995;

* Elation when the Germans authorized a clean-sheet approach to the third-generation model in 1996;

* Frustration in convincing the Germans that a spin-off of BMW's X5 SUV wasn't the appropriate recipient of Land Rover's painstakingly nurtured DNA, and,

* Utter amazement to see Reitzle leave BMW then foster the sale of land Rover to his new firm Ford.

Through at all, Sneath held his ground to make sure this child of too many parents survived the birthing process to be a true Range Rover, a machine just as comfortable cruising at 100 mph as it was crawling over boulders at a walking pace. The fact that such a dual personality was achieved with hardware that seems far more BMW-like than any previous Solihull-built product is the ultimate proof of Sneath's persistence.

"Visual Superiority"

Historically, Land Rovers have sturdy steel-rail backbones, floppy bodies, stubbornly rigid axles, and powertrains with a lineage back to King Arthur's court. BMW wanted none of that and, as it turns out, Sneath agreed that a step change in the blueprints was a prerequisite to achieving his ambitious on- and off-road performance goals. So what emerged is, for all intents, an eleven-tenths, second-generation X5 that surpasses BMW's previous best in the SUV realm.

Understanding the fundamental virtues of both BMW'S X5 and Mercedes-Benz's M-Class SUVs was crucial to Reitzle's desire to create a truly superior Land Rover flagship. Balancing on- and off-road capabilities was certainly an ambitious challenge. But what this product also needed, reckoned Reitzle, was presence - a visual superiority. So the new model is purposely a size larger than its predecessor. Riding on a 113.4-inch wheelbase (larger by 5.3-inches), it's longer by 9.3 inches, wider by 2.6 inches (not counting door mirrors), and taller by 1.8 inches. Slotted neatly in size between the Ford Explorer and a Lincoln Navigator, the new Range Rover is more substantial but not too ungainly to thrive off-road.

Steel-Aluminum Stiffness

Land Rover engineers waved goodbye to body-on-frame construction while meeting ambitious targets for wheel travel, approach and departure angles, and ground clearance. They claim their structure is both the stiffest and the largest unibody in production anywhere, with a torsional stiffness of 24,000 pounds-feet-per degree and a first-order bending-mode natural frequency of 28 Hertz. High-strength steel was used to triple the stiffness of the outgoing model while providing 7,000 pounds of trailer-towing capacity and an ability to withstand 12,000-pound snatch-recovery loads (punishment applied when a recovery vehicle breaks Mother Nature's mulish grip with momentum transferred via a nylon tow strap).

To minimize the weight gains inevitable with a larger, more powerful, and more sophisticated model, Land Rover engineers used aluminum extensively. The inner and outer hood panels formed in-house are allegedly the auto industry's largest aluminum stampings. The doors are a collection of die-castings, stretch-bent extrusions, and aluminum stampings bonded with epoxy structural adhesive in a Dura Automotive Systems satellite facility. The front fenders are also aluminum. A total mass savings of 110 pounds is attributable to the use of aluminum instead of steel. The net weight gain over the retired Range Rover is approximately 500 pounds.

Underneath, at first glance the strut-type front suspension and multi-link independent rear axle look like pages from BMW's standard play book. Closer inspection reveals significant refinements in line with Land Rover's finely-bred DNA. For example, BMW and other makers have adopted aluminum suspension components verboten at Land Rover because of fears they are susceptible to cracks and breakage in cruel, rock-infested off-road environments. For that reason, low-hanging control arms remain robust steel forgings or fabrications. Air suspension is retained, albeit a new system with added sophistication (see sidebar).

Foundation brakes have BMW-supplied vented front and solid rear brake rotors and ContiTeves calipers. The power-assisted rackand-pinion steering gear is a ZF speed-sensitive Servotronic unit

Major Powertrain Changes

BMW was obviously light years ahead of the pushrod V-S Land Rover requisitioned from GM in the 1960s. The 44-liter dohc V-S under the '03 Range Rover's hood is the same basic engine powering BMW's current 5-Series sedan and X5 SUV. It has a few pertinent changes to satisfy the Brit's penchant for off-road ruggedness. The air intake is raised to thwart water ingestion in the fording mode. A new oil sump meets LR's requirement for maintaining oil pressure on 35-degree side slopes and 45-degree grades. Various seals have been upgraded from BMW's specifications to inhibit dust intrusion. The drive-by-wire throttle system has two modes - normal for on-road use, augmented by a slowerresponding calibration for creeping off-road.