4WD and AWD
Getting the best grip on the road or terrain is what will get you moving forwards from A to B in the shortest time. Ever since the invention of the first cars, two-wheel-drive has been the mainstay for delivering the engine’s power out to the wheels. At first, two-wheel drive was usually via the rear wheels, as it was much simpler to run a drive shaft from the engine at the front of the car back to the rear wheels to get grip from the rear wheels and to let the front wheels have the job of steering the vehicle.
In saying that, there is also history of 4WD being experimented with back as early as the late 1800s in combination with a traction engine, and, of course, in World War II, the 4WD Willys Jeep was a game-changer.
Once mechanical engineering and quality improved over time, the concept of having the engine over the front axle and the front wheels as the driving wheels as well as for steering the vehicle lowered production costs. A combination of rear-wheel-drive and front-wheel-drive cars were available as a matter of course right up to the 1970s and 1980s. Through the 1990s up until the present day, it was more common to see front-wheel-drive cars for everyday driving.
However, it was the 1980s that proved to be a very innovative period in automotive design and mechanical engineering. The greatest advancement in road-going cars was arguably the use of four-wheel-drive to establish greater levels of grip. As racing and supercars demanded faster cars, the need to control all that power (and actually make better use of it) was essential for winning, especially as there was an ever-increasing number of high-performance cars being pulled out of roadside hedges or being wrapped around power poles.
Enter Audi. Audi’s Quattro technology marked a significant moment in high-performance cars’ and supercars’ history. The Audi Quattro’s technology was essentially the dawn of the modern supercar’s 4WD system, and when Audi entered the World Rally Championship in 1981 with their Audi 80 Quattro car, they were unbeatable. The second-place car was over twenty minutes behind the race-winning Audi!
What is the difference between 4WD and AWD?
This is a good question to answer, because there are numerous new cars of all shapes and sizes available with AWD or 4WD. Generally speaking, four-wheel-drive (4WD) is the older off-road system that has the power split 50:50 front to rear. Add a diff-lock into a 4WD system, and these are off-road kings. Four-wheel-drive can be disengaged so that just two-wheel-drive (2WD) can be used on easier terrain, including for when you’ve finished your off-road adventure and you just want to head back home on the tarmac with 2WD only.
The basic principle of an all-wheel-drive (AWD) system is that it can deliver the optimum level of torque to each wheel individually, thus giving the best possible drive and traction. AWD systems tend to be permanently engaged, but with the power split front to rear, along with individual wheels being variable according to what each wheel is sensing and therefore demanding at the time. AWD systems are more complex in that they use sensors which send precise information and values of each wheels’ speed, torque, wheel slip/spin, brake pressure, and steering input to the AWD’s central control system. The control system then adjusts the torque supplied to each wheel.
Land Rovers and many other new serious off-road vehicles use AWD systems with various diff-locking abilities, which also make them real off-road kings. Four-wheel-drive systems are simpler in nature and are thus simpler and cheaper to fix than more complex AWDs. That said, many manufactures like Subaru know how to make solid, dependable AWD systems for their cars and SUVs that are mainly aimed at everyday on-road use and trips up to the ski fields, but with the credentials for performing well even in some fairly serious off-road terrain.
If you live in a part of the world where gravel roads and rainy seasons collide, then an AWD vehicle with decent ground clearance should be parked up your driveway. If your day includes a trek out to the building site, feeding out to stock, or traversing any serious off-road terrain, then a heavy-duty 4WD or AWD vehicle will be your companion. The good news is there are plenty of these sorts of vehicles about, many of which can be bought new at a good price via Private Fleet.
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