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Light-weight All-wheel Drive 1
Generally speaking, vehicles with internal combustion engines have, two-wheel drive, although in the past, there have also been three-wheelers where the single front wheel was driven. The two driven wheels are,
with exceptions, not directly coupled to each other, that's why, without a limited slip differential, a driven wheel without traction, seriously hampers driving.
In difficult terrain or on steep climbs, even two driven wheels can be overtaxed, which supplies us with the first advantage of all-wheel drive. However, this alone does not explain the relatively high sales figures of
such models. Some buyers also consider the high towing capacity to be important.
An interessting fact is that, in the USA, SUVs are more frequently two-wheel drive vehicles than here in Germany. Also, for many years it was in fact England, where the highest sales were recorded and not Austria or
Switzerland. So obviously, the Range-Rover provided the breakthrough for a 'Jack-of-all-trades', equally suited for the hunt and for the visit to the opera.
A certain amount of psychology may be the explanation for the envisaged purchase. In the USA they even more reserved for the upper range, for a high percentage of European car buyers it's a dream. The wish to
own an all-wheel drive or SUV, is often justified by the alleged higher safety factor, perhaps what is really important, is the prestige. It might be interesting, in the course of this text, to have a closer look at this
phenomenon.
Let's put the question to one side and get back to the history. One has to start somewhere, which is why the following drive-types from the early years of the automobile, will be purposely left out:
- All-wheel drive
steam engine vehicles,
- all-wheel drive vehicles with electric wheel-hub motors,
- all-wheel drive utility vehicles,
- prototypes or small series vehicles with all-wheel drive.
We would like to place the beginning of a really large series of all-wheel drive motor cars at the year 1940, and start with the Willys Overland Jeep (World-War II Jeep). Thereby, we'll interpret the expression 'motor car'
rather generously, to include those having a gross weight of up to 3500 kgs.
It's quite unbelievable, that the American industry under the pressure of the events after 1940, and without a lot of experience in this field, could construct and produce a vehicle in large numbers. Willys Overland depended on the Ford works to be able to achieve this, they also temporarily saved the company from certain ruin.
A conservative concept was chosen for this construction. The torque for the rigid front axle was diverted from the so-called standard-drive (engine up front, rear-wheel drive), no different from the all-wheel drive trucks
of that time. A further important aspect would be, the greater ground clearance which would mostly distinguished it from the SUVs.
Even though in the end, the Bantam- and Willys Overland companies could not survive independantly, the jeep has made it's mark, and is justifiably regarded as the first light-weight all-wheel drive built in large
series. We however, will move on to the next landmark, the Land Rover, Britain's answer to the Jeep in peacetime. 05/11
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