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THE RANGE ROVER CONCEPT

When the first Range Rover was produced in 1970, it started an entirely new trend in four wheel drive vehicles. It blended supremacy over all competitors off road with comfort and convenience on road. With a production run lasting twenty six years, the original Range Rover "Classic" was a unique vehicle, and the only one ever to be exhibited in the Louvre as a work of art. Land Rover Owner International Magazine voted it as the best Land Rover ever in 1996. One judge called it the best vehicle built by anyone, anywhere, ever. Successive newer models have remained the benchmark against which other SUVs compete. Although no longer exhibited in the Louvre, Range Rovers retain the title of King Off The Road while steadily improving on-road performance and refinement.

 

The success of the original Range Rover was due mainly to its inspired mechanical design which gave it the best performance of any 4X4 both on and off the pavement. While many think of it as just a luxury version of the generic 4X4, its real secret was the extraordinary engineering innovation hidden behind the wood and leather trimmings. It possessed a massive box section ladder frame, prodigious ground clearance, a smooth V8 with good low end torque, and last but definitely not least, a brilliant suspension design that rival manufacturers have still not equaled. The result was outstanding all-terrain traction as well as the smoothest ride of any 4x4. Later Range Rover models remain true to the original concept using fundamental design innovations that keep them far ahead of competitors in their enormous breadth of on and off road capability.

REFINEMENTS AND NEW MODELS

In the 1980's and 90's while the original Classic Range Rover was still in production, other manufacturers scrambled to catch up. But refinements to the original model still kept it way ahead of the field. Improvements included suspension re-tuning, an automatic viscous locking center differential, the first ABS system designed for off-road use, and electronic traction control. Just when others started copying the coil suspension, it was replaced with electronically controlled air-adjustable suspension which could be raised and lowered over a 5 inch range.

In 1994 a completely new model replaced the Classic. The Mark II/P38's streamlined body shape incorporated even more luxury with sophisticated computer controlled functions. An improved air suspension, stronger chassis, manual control of low range ratios, more ground clearance, improved dust sealing, and a host of other new features assured retention of its place as "King Of The Road".

In 2002, an even more drastic redesign was completed, using a much stronger monocoque body and chassis with independent suspension, both concepts were hitherto a heresy in the 4X4 world. The Range Rover Mark III/L322  had improved ground clearance, even more wheel travel, and cross-linked air springs for more traction and a softer ride off road. A BMW V8, shift-on-the-move transfer case, and many other refinements improved both on and off-road manners.

A few short years later the "Sport"/L320 was added in 2005 alongside the "Real" Range Rover, with a 400 HP supercharged option that dispelled any remaining myths about Range Rovers not keeping up with other SUVs on the pavement. True to tradition, it incorporates such an array of off-road features and abilities that it leaves its competitors in the dust or in the ditch. 

So what does the future hold for Range Rover? Each successive update has assured that the Range Rover remains the world's most capable vehicle. Although its luxury features are famous and its on-road performance is continuously improving, the thing that distinguishes Range Rovers from other luxury SUV's in today's crowded market is their supreme off-road ability. The unparalleled breadth of capability means it is never out of place whether at the most exclusive city club or in the roughest back country terrain. With the Evoque/L538 opening up a new chapter for lightweight, fuel efficient models and the Mark IV/L405 being rolled out for the 2013 model year there seems to be no limits to Range Rover's technological and design advancement.

PERFORMANCE ON AND OFF ROAD

The Range Rover design concept was one of excellent performance on the pavement and superlative performance off road. In 1970, its acceleration and speed were superior to many conventional cars. As late as 1985, a diesel-powered Range Rover "Bullet" Record Breaker broke 27 diesel vehicle speed records, averaging over 100 mph for 24 hours. By the 1990's, although speed and acceleration had improved, they were not exactly a selling point, as competitors introduced more spritely SUVs that could leave a Range Rover standing at the traffic lights. Off the pavement, however, Range Rover performance has always been nothing short of staggering, and is an eye opener to anyone not familiar with the vehicle. It runs circles around virtually any other 4X4, including many modified ones. Over the years it has maintained or even increased this edge, being one of the few actually designed from the ground up for serious off-road ability. Other manufacturers, knowing that most owners never take their vehicles off the pavement, developed low slung SUVs and stiff suspensions tuned for car-like handling. The Range Rover retained its soft long travel suspension, and even increased available ground clearance with adjustable air suspension.

The design of the Range Rover Mark II/P38 was intended to improve pavement performance and handling to attract buyers from luxury car marques, while retaining supreme off road performance. A new streamlined shape allowed faster, quieter highway cruising, and lighter axles with suspension refinements improved handling. Several new off-road features were also added and magazine comparison tests uniformly acclaimed its continued effortless superiority in that arena.

The even more radical redesign of the Mark III/L322 Range Rover further improved off-road capability while endowing the vehicle with truly car-like on-road manners. Independent suspension and a monocoque body gave the needed on-road refinement, while increased ground clearance, wheel travel, and innovative cross-linked air springs vaulted the new vehicle ahead of its off-road competitors yet again. In the July 2002 Land Rover Owner International magazine "off-road-only" comparison test report shortly after its introduction, the new Range Rover bested even the formidable Land Rover Defender in off-road performance.

With the addition of the Sport/L320 to the Range Rover stable the evolution of performance has continued. As the name suggests, this model emphasizes sporty performance, but off-road prowess has by no means been neglected. With its reduced bulk and 300 or 400 horsepower engine choices, it is no slug on the tarmac. Off the pavement, it can run circles around any other "Sporty" utility from Mercedes, Porsche and the like. The sophisticated Terrain Response system first introduced in the Discovery 3/LR3 is included, along with optional locking rear diff, 4-wheel traction control, Hill Descent Control, and a suspension that can be lifted in extremes 3 inches above the "High" position normally used off road.

THE RANGE ROVER SECRET: SUSPENSION DESIGN

Range Rovers have always been distinguished by innovation in suspension design. The Classic Range Rover was able to use exceptionally soft springs, while retaining a 1600 lb payload capacity, by virtue of the Boge self-leveling strut fitted to the central A-frame link on the rear axle. This is, in effect, a variable rate self-adjusting air spring which provides a restoring force on the center of the axle to compensate for load, allowing very low spring rates to be used at the road wheels. This results in maximum possible traction on uneven terrain.

Why does a soft suspension give better traction? This is a secret that other 4x4 manufacturers and aftermarket suspension builders have apparently never learned. When a wheel droops even an inch or two on uneven terrain, that wheel is "unloaded", i.e. its ground contact force is reduced, in direct proportion to the stiffness of the spring and anti-roll bar. Any loss in ground contact force reduces available traction at the wheel in question. With an open differential on the axle, traction is lost at both wheels simultaneously.

Conventional and "lifted" 4x4s overwhelmingly use leaf springs or stiff coils with anti-sway bars tuned for flat high speed cornering on pavement or supposed "heavy duty" use off-road. Aftermarket "upgrades" invariably include even stiffer springs, shocks, bushings and/or anti-sway bars. The net effect is a very stiff suspension that not only provides less maximum wheel travel, resulting in wheels lifting off the ground in very uneven terrain, but much reduced traction even in mild off-road situations requiring only modest vertical wheel movements. This is why the conventional dogma dictates that serious off-road vehicles must use "lockers" on the differentials to maintain traction. Lockers force both wheels to rotate at equal speed, transferring all the torque to whichever side has the grip. They therefore greatly increase stress on the drivetrain components, and have adverse side effects on steering control. On newer Range Rovers, any lost traction is restored through a sophisticated system of electronic traction control. This senses when a rear wheel starts slipping and pulses its brake, effectively transferring half the engine torque to the opposite, gripping wheel. The combination of soft suspension and electronic traction control is formidable. The system gently equalizes torque distribution to the two wheels, whereas the locker can suddenly transfer 100% torque to one wheel, breaking parts with notorious regularity.

The redesigned Range Rover Mark II/P38's electronically controlled airbag suspension is another innovation in 4x4 underpinnings. Although slightly firmer than the early coil spring design, it is plenty soft enough to cause complaints about body roll by automotive journalists. The same journalists, however, rave over its ability to soak up gaping holes in the road like a Mercedes negotiating speed bumps. Axle articulation in stock form easily outclasses other SUVs. The ability to raise the vehicle 1.6 inches above normal provides more clearance for off road use, while conversely the body is lowered an inch in highway mode to stabilize the vehicle. When it becomes high centered, the suspension hoists itself above even the "high" setting to try and break it loose. The maintenance of constant height under all load conditions is a boon for off road use when the vehicle is often heavily loaded. No sagging in the rear, or reduction in clearance. Also, the progressive nature of air springs reduces the chance of "bottoming out" when hitting a bump too fast.

In the Range Rover Mark III/L322, the designers debunked the traditional assumption that independent suspension is unsuitable for serious off-road use. Careful design resulted in stupendous vertical wheel travel that easily bests any other production vehicle, 10.75 inches in the front and 13 inches in the rear. Off-road, the air suspension is programmed to operate like a beam axle, so that a rising wheel forces its opposite member downwards, maintaining clearance. This is achieved by opening valves that link each left air spring to its right hand opposite number, so that upon compression of, say, the left spring, its air is forced into the right one. This also has the effect of reducing the effective spring rate to near zero, hugely increasing the available ground contact force and traction on the drooping wheel. A third benefit is the much softer ride achieved off road, allowing faster progress and lighter impact. A full 2-inch lift in off-road mode gives 11 inches of clearance and reduces the spring rates.

Nobody can accuse the Range Rover Sport of having a soft suspension, but it makes up for it in sophistication, as an off-road drive of it shows. The traction control, center and rear diff locks, hill descent control and Terrain Response system make it hard to stop. Its suspension, like the P38's, has the "extended profile" feature that senses when the vehicle is grounded, and raises the suspension another 1.5 inches. Beyond that, the driver can raise it another 1.5 inches by holding the "up" button.

For additional information on Range Rover suspensions and modifications please see our Suspension Details Page.

ADDITIONAL OFF-ROAD DESIGN FEATURES

Innovative suspension is not the only secret behind the Range Rover's legendary off-road prowess. The solid construction of the 14 gauge box section chassis, the axle housings and linkages, and other underbody parts means the Range Rover will withstand exceptionally severe off-road treatment. The transfer case uses relatively high numerical gear ratios, enabling the use of lower numerical ratio gears in the axle differentials for extra strength. High underbody clearance provides extreme breakover angles. If the vehicle does become high centered, the electronic air suspension on later models senses this condition and raises the body even higher to set it free.

Drive along behind most 4x4s and you will see the rear shock mounts hanging vulnerably well below the axle, in a perfect position to be snagged on rocks. The Range Rover's shock mounts are positioned so as not to cause such problems. Similarly, on most 4x4's the rear differential is in the middle of the axle while the front diff is off to one side, effectively reducing usable clearance over rocks and ridges since one or other differential, or a shock mount, is almost certain to hit something. The Range Rover's differentials are both positioned in line, offset from the center, so that foot-high obstacles can pass straight under the vehicle.

Many other features distinguish Range Rovers, old and new, from SUVs designed mainly for looks. Mud deflectors are fitted to all the brakes, and mud flaps are standard on many models. The V8 has an exceptionally flat torque curve from very low speeds, giving good low speed crawling power, and the throttle has unusually long travel, for delicate adjustment in off-road situations. The handbrake operates on the driveshaft and locks all four wheels which is vital in tricky off road maneuvering so you can get out and take a look at your predicament. The high seating position and short hood make it possible to see obstacles on the ground very close to the front of the vehicle. The transfer case differential automatically and progressively locks when it senses a difference in front-to-rear axle speed indicating slippage of a wheel.

On the Mark II/P38, the automatic transmission can be locked in any gear while in low range and shifting between high and low range is simplified by a new "H" gate single shifter design. Ground clearance is increased under the differentials, components are better tucked up between the chassis rails to give a cleaner underbody, and the air intake is further raised for a dry air supply when fording. The V8 engine has undergone testing in extreme off-camber positions for extended periods, and prototypes driven for hours at high speed behind dust-making machines on dirt roads to test the filtration system which is designed to eliminate the ingress of dust into the cabin. The chassis is substantially strengthened, including radius arm mountings which are much less vulnerable to being knocked out of alignment by a hit from a rock. The fuel tank is in a more protected position and is designed to deform substantially under impact from the ground, without stopping the fuel pump from operating.

On the Mark III/L322, yet more off-road features were added. Wheel travel was increased to staggering levels, combined with the innovative cross coupling of the air suspension. A cleaner underbody with 11 inches of clearance in high profile has Kevlar protection and very few vulnerable protruding parts; even the normally vulnerable exhaust outlets are tucked up under the rear of the vehicle so they are flush with the rest of the body. Other improvements include increased approach and departure angles, more ground clearance, a torque sensing center differential, a shift-on-the move transfer case, a dual-program throttle tuned for longer travel in low range, power folding mirrors to avoid trees and other obstacles, a heavy duty front recovery loop, Land Rover's patented Hill Descent Control, and All-terrain Dynamic Stability Control to prevent skids and slides on slippery surfaces. In combination with the clean underbody and excellent ground clearance, all these features make the Mark III quite unperturbed when the terrain turns awful. Most of these features are incorporated into the Range Rover Sport as well. A Range Rover is also one of the very few production vehicles that you can order with a winch.