AWD 4WD vs AWD: what’s the difference
What are the differences between two similar systems all-wheel drive AWD and 4WD?
So what is the difference of the four-wheel drive and all-wheel drive? Whether it is at all and what the AWD system is better to give preference? The answer to this question will be much more difficult than you would expect. Whether system plug-in, permanently employed or they are forced if necessary? Connect upon Commission of certain factors or included previously in automatic mode? Used in these hydraulic clutch, electromagnetic clutch or a completely different system? If they are included by using a lever, turn of a dial, pressing a button or just magically begin to work when needed? To answer these questions, delve into the history and nuances of each system individually on the example of foreign experience of creation of such record.
In the late 80-ies, the AWD cars were simple mechanisms, high reliability, and is a purely utilitarian means of transportation. Often, they drove the hunters, farmers, and cattle drovers. These people were not by liposuction and could in any conditions and in any thick mud simple to connect the hubs to activate the front axle. However, over time and thanks to the popularization of SUVs among the urban population, which did not want to swim knee-deep in mud and get dirty hurl, all-wheel drive brethren, the beginning of its evolutionary development towards democratization and availability of all-wheel drive systems, giving the possibility of a simple, untrained people to enjoy all the benefits of AWD systems.
It’s funny to hear, especially considering the original purpose of such systems and vehicles equipped with them.
History
All-wheel drive system on the car was not invented yesterday. Their origins are rooted in the nineteenth century.
In 1893, the English engineer-inventor bramah Joseph Diplock designed and applied all-wheel drive system for the tractor of the tractor. Design even by today’s standards command the world’s respect in those years was top of engineering art. Off-road tractor-terrain vehicle conquered using three differentials and four-wheel drive system with four (!) steered wheels.
The first sports car with the internal combustion engine was the Spyker 60 HP, which was created by the brothers from the Netherlands Jacobus and Hendrik-Jan Spyker, as a two-seater sports car for racing up a mountain (hill klajmbinga). This is an important milestone in the development of all-wheel drive systems occurred in 1903.
Then there was German, unprepossessing in appearance Dernburg-Wagen, built by Daimler-Motoren –Gesellschaft. It was followed by a whole galaxy of different prototypes and the search for reliable, low maintenance and optimum design.
In the prewar years, before the Second world war, Mercedes-Benz, in cooperation with BMW, worked on the military series “G”. Attempts were rewarded with the creation of unusual and unique cars. But a real, well-deserved reputation received another legendary car of the war years, who came from another continent, which side by side passed military in the ways of our grandfathers bombed by impassable roads of the Bryansk region, Moscow region, Belarus, Poland and finally Germany itself, – Jeep Willys.
Control system all-wheel drive was simple and effective. One lever included jeep four-wheel drive, another selector, you can choose high gear, neutral or low gear.
All-wheel drive system has evolved over the 1950-ies and 1960-ies. Appeared external locking front hubs, which gave the ability to disable the front axle to improve fuel efficiency and speed performance. In 1963, the family four-wheel drive Jeep Wagoneer got an automatic transmission. Ten years later, the updated model was equipped with a system Quadra-Trac, the industry’s first automatic system of permanent four-wheel drive.
All-wheel drive goes for cars. About the same time when American engineers developed the “heavy artillery”, the Japanese tried to instill in all-wheel drive system for passenger cars. Symbiosis off-road drive and the cars body was embodied in the Subaru Leone. Model appeared in 1972. Its distinctive features was the system with all wheel drive, good helped the owners in poor weather or road conditions.
In 1980 AMC released the Eagle model set the benchmark for AWD passenger cars of those years. The model was equipped with a permanent automatic all-wheel drive. At the same time, there is a true legend, the firstborn of the Audi Quattro with permanent all-wheel drive was first used not to improve off-road qualities, and to improve traction on the road, handling and performance in sport.
1983. Jeep has a new system Select-Trac. Since then, the Jeep could travel in four-wheel drive version at high speed on ordinary roads without devastating consequences for the transfer case. Next year, the new Jeep Cherokee was presented with more advanced wheel drive system Command-Trac, which allowed to connect the front axle on the move.
Since the mid 90-ies, almost every automaker in the United States began to create SUVs (sports utility vehicles). They were made simple were taken frame-based pickup truck and mechanical 4WD. Technically, the insides have remained archaic, but they worked in a new trendy body.
The sensational popularity of SUVs has led many automakers to go on about marketers and consumers. Body began to do the carrying, frame construction gradually began to be abandoned. A class of crossovers, fast-paced and conquer new segments of the market. Among them prevail AWD system*.
*All-wheel drive (All-wheel drive, AWD) is capable of transmitting the power between both axles, as well as from wheel to wheel. Much more convenient automated all-wheel drive system, which gives almost all the same benefits as classic 4WD, but with less amount of inconvenience for everyday use. However, for convenience have to pay the lower reliability of the drive.
4WD
The 4WD system drive, usually intended for use in moderate or heavy off-road. On cars with this system there is a set of low-range gears and a manual or automatic transfer case.
Vehicles with 4WD can often be distinguished by special attributes: higher ground clearance (for the expensive versions of the SUV we can talk about height-adjustable suspension), good angles of cross, they are the same angles of entry and exit front – to-rear, which gives the opportunity to climb and descend inclines and move over obstacles.
Vehicles installed reinforced suspension and off-road tires, additional systems increase traction, such as differential lock, assistance systems while driving off-road (modern Toyota) and starting up the hill from the place, and disconnecting sway bars.
Some 4WD systems, for example, as Gelandwagen, additionally blocks a Central differential, which significantly increases the chances of overcoming the serious off-road.
Differentials can be controlled through electronics, mechanical or hydraulically.
4WD all-wheel drive system could detect almost all SUVs of the past. Still many manufacturers of pickups have use of a 4WD model, but the trend is that they are becoming more and more rare. Even the once brutal military models moving to mainstream AWD! Therefore, the ancestor of modern AWD systems can be considered an endangered species.
AWD
All-wheel drive is a type of all-wheel drive, where the power and torque sent to both axles, redistributing torque from the axle or wheels with less traction to the wheel with more. The AWD system is designed to improve traction on the road/ground and increase performance in all weather conditions, and increased possibilities of automobile on the easy or middle road.
One of the most common AWD installations includes a differential between the front and rear drive shafts like some of the 4WD systems of the past. On some vehicles, uses constant all-wheel drive, which continuously sends power to all four wheels, while other car, one of the axes enabled if it is needed. In such cases, crossover, or passenger car vehicles (like the E-Class All Terrain) rides a monodrive.
The desired torque on the axis is often achieved through the use of electronically operated traction control brakes when the AWD system senses wheel slip or sees the difference in speed of rotation of the wheels, work the brakes and going on the controlled distribution of torque. Almost all modern all-wheel drive system work without driver intervention, they are controlled by an endless chain of computer codes, using very sophisticated algorithms that monitor steering control, throttle and braking mechanisms. The purpose of all this technological nagymajtenyi, the sole to improve grip.
System of a full drive DYNAMAX on the new Kia Sportage has it all and even more, for example, it has sensors that read the road ahead, proactively identifying areas of ice, holes or water.
Can system full-time 4WD and AWD coexist in modern conditions?
The four-wheel drive vehicles continue to become more popular; the main argument of apologists of the front or rear drives, fuel efficiency, eventually goes by the wayside, pales against the background of the advantage in handling and safety.
Some buyers are still required benefits drive type 4WD such as a wider range of options for towing and heavy loads, operation of the vehicle on steep grades or on rough terrain, but for most consumers it AWD system provides the greatest benefit and lowest cost.
How will the AWD system in the future? It may be separate electric motors in each wheel, created by the type and likeness of the car, created by the genius Ferdinand Porsche in 1899? Maybe someday, but not now.
AWD system the next generations will be evolutionary, not revolutionary. A research project initiated by Jaguar Land Rover considering all-wheel drive system that will enable vehicles independently to carefully determine the location and severity of road obstructions such as potholes and open manhole covers to alert drivers and configure your car for a safer, smoother drive.
AWD systems of tomorrow will rely on advanced technologies that will help vehicles improve off-road capability and a little closer to what I was capable of their famous ancestors-wheel-drive 4WD.