Active vehicle safety: which type of drive is best? Four-wheel drive: operating principle, systems and technology.

At first glance, the principle of operation of the transmission of an all-wheel drive car is simple: the torque from the power unit is distributed between the four drive wheels. Such a car is very convenient due to its pronounced advantages associated with unpretentiousness to the quality of the coating under the wheels. On a dirt road, on ice, on wet country terrain or on a highway in a heavy rain, an all-wheel drive car will show itself at its best. Plus, on it you can not be afraid to move off the asphalt surface and cross the terrain without even a hint of roads, and on the asphalt, the four-wheel drive makes itself felt with a good start and acceleration, with practically no slippage.

But sometimes incidents occur, which, it would seem, are difficult to explain due to the advantages that all-wheel drive cars have. It so happens that the driver sits behind the wheel of an SUV with an impressive ground clearance, and the car got stuck in a "mess" and lay on its belly.

Interesting to know! In 1883 american farmer Emmet Bandelier patented a design similar to the current all-wheel drive system.

Of course, there can be many reasons for this, the most common of which is, as experienced drivers jokingly put it, "the gasket between the steering wheel and the seat." But it also happens that the transmission of the "all-terrain vehicle" is not supposed to cope with the tests. And then reasonable questions arise: "Why can't they cope?", "And which one can cope?" We will talk about this further in the provided material.

Manual 4WD (Part-Time)

This type of transmission can rightfully be called the "firstborn" among all-wheel drives. The principle of its operation is the rigid connection of the front axle. Thus, all wheels rotate at the same speed, and there is no center differential. The torque is distributed equally between all wheels. Anything to do in this case, so that the axles rotate at different speeds, will not work, except to penetrate into the "womb" of the car and install a new differential.

In the meantime, it is not recommended to cut in traffic with the front axle connected. Even if you move straight in a low gear for short distances, nothing terrible will happen, but if you need to turn around, then the resulting difference in the length of the bridge paths becomes an obstacle. Since the distribution is 50/50% between the axles, the power surplus comes out only by wheel slip of one of the axles.

On sand, gravel or mud, the wheels can slip if necessary, and nothing will interfere with them, since the grip on surfaces is weak. But if the weather is dry, and you are driving on an asphalt road, then the power will have nowhere to go, as on off-road. Thus, the transmission is exposed to increased loads, rubber wears out faster, handling deteriorates and directional stability is lost at high speeds.

If the car is used more often off-road or is generally purchased only for cross-country driving, then the all-wheel drive system with forced connection of the front axle will fully meet your expectations. The bridge connects immediately and hard, so you don't have to block anything. The design is very simple and reliable, there are no locks and differentials, there are no electric or mechanical drives, there is no unnecessary hydraulics and pneumatics.

But if you are an urban "dandy", value your time and do not want to bother about weather conditions and alternating sections of the city with its loose and slippery road surfaces, treacherous deep puddles, then the version of this all-wheel drive system is absolutely not suitable for you. If you move with the front axle always forcibly connected, then this is fraught with wear and tear with subsequent damage, it is not very convenient to constantly manipulate it, and you may not have time to connect it at all.

Cars with Part-Time: Suzuki vitara, Toyota Land Cruiser 70, Great Wall Hover, Nissan patrol, Ford Ranger, Nissan navara, Suzuki Jimni, Mazda BT-50, Nissan NP300, Jeep Wrangler, UAZ.

Permanent four-wheel drive (Full-Time)

The drawbacks of plug-in all-wheel drive were the root cause of a newer invention - permanent all-wheel drive, which is devoid of all the problems that Part-Time had. This is the same uncompromising "4WD", which is devoid of any "and if" there: all the wheels are driven, between the axles a free differential, which releases the accumulated excess power thanks to the scrolling of one of the gear satellites, which contributes to the movement of the car with permanent all-wheel drive. The main nuance of cars with this type of all-wheel drive is slipping. If the car starts to skid with one axle, the second is automatically turned off.

Now the car has turned into furniture or a house, as you wish, in general, into real estate. How does this happen? If one wheel starts to slip, interwheel differential disables the second, and the second axle is also automatically disabled by the differential, but already by the center one. Of course, in reality, the stop does not happen so quickly. Movement is a dynamic process, therefore, there is a power reserve, inertial force. The wheel turns off, moves by inertia for a couple of meters and turns on again.

But in this case, the car will sooner or later come to a standstill somewhere. Therefore, in order to preserve all the off-road qualities of the "rogue", such cars, as a rule, are equipped with one or two forced locks center differential... It is very rare to see a factory lock in the front differential. It is installed separately if desired.

But the permanent all-wheel drive system is also far from ideal driving performance on asphalt roads. Such cars drive, let's say, it would be better. In critical situations, the SUV pulls out of the corner and does not immediately respond to steering and gas puffing. Drivers of these vehicles require special skills and excellent vehicle feel.

To improve handling, they began to install interaxle self-locking differentials with a forced locking system. Different automakers used different solutions: some with a Torsen differential, some with a viscous coupling, but the task for all is the same - to improve the car's handling, and this requires a partial differential lock.

If one of the axles starts to slip, the self-locking mechanism is triggered, and the differential does not affect the second axle, which continues to receive torque. A number of cars were also equipped with a self-locking mechanism for the rear axle differential, which had a positive effect on the sharpness of control.

Among cars with permanent all-wheel drive, one can distinguish Toyota Land Cruiser 100, 105, Land Cruiser Prado, Land rover Discovery, Land Rover defender, Lada 4x4.

Torque on-demand (AWD) automatic all-wheel drive

Time and the inquisitive minds of automotive engineers have done their job by developing the all-wheel drive system into something new with the introduction of electronically controlled systems with the redistribution and transfer of torque. As a result, there were stabilization and directional stability systems, traction control systems, as well as systems that distribute torque. All of them are implemented using the involved electronics. Than more expensive cost the car and its more modern filling, the more complex schemes are applied to it.

This is tracking the steering angle, body rolls and speed, up to how often the wheels oscillate over a certain distance. The car carries out the most complete collection of information about its behavior while driving. The ECU processes it and regulates the transmission of torque between the axles through an electronically controlled clutch, which has changed the differential. In modern sports cars, this invention has become quite noteworthy.

Today, electronic systems can be called almost perfect in their behavior. It is only necessary for manufacturers to add several new sensors and parameters, thanks to which the system works ahead of the curve.

But here, too, there are nuances of use: given type All-wheel drive transmission is suitable for operation only on asphalt roads with rare interspersed with symbolic off-road, primer, for example. Basically, electronic clutches, when slipping off-road, begin to get very hot and fail. And for this you do not need to plow the tank tracks for hours, ten minutes of skidding on the ice is enough. And if it is overheated systematically, then breakage cannot be avoided, as well as expensive repairs.

The “cooler” the system, the more susceptible it is to breakdowns. So you need to choose a car wisely, having determined for yourself on which routes you will ride it. Don't go to extremes: if it's an SUV, then only into the forest and the village, and if it's a passenger car, then only around the city. There are plenty of cars from this segment that are versatile in their driving characteristics. But also without fanaticism. On passenger car you can, of course, go to a country road, but which one and which one is another question.

If one of the ABS sensors breaks the wiring, then the entire system will fail at once and will not receive information from the outside. Or gasoline was not poured best quality - and that's it, the low gear does not turn on, there is a trip to the car service ahead. Or it may happen that the electronics will put the car in service mode, completely disconnecting all systems of her life.

Among these cars, it is worth highlighting Kia sportage (after 2004 onwards), Cadillac escalade, Nissan Murano, Nissan x-trail, Ford explorer, Toyota RAV4 (after 2006 onwards), Land Rover freelander, Mitsubishi Outlander XL.

Multi-mode (Selectable 4wd)

This system is perhaps the most versatile in relation to all-wheel drive with its various manipulations: it can be activated manually or automatically, as well as forcibly deactivate the rear or front axles. The Selectable 4wd system does not increase fuel consumption. The leader in terms of fuel overspending is the part-time vehicles mentioned at the beginning.

Some cars with selective transmission, which can be called permanent all-wheel drive, with the ability to forcibly disable the front axle, stand apart. On such vehicles, the transmission combines part-time and full-time. Among them Mitsubishi pajero, Nissan pathfinder, Jeep grand Cherookee.

In "Padzherik", for example, you can choose one of several transmission modes: 2WD, 4WD with an automatic central differential lock, 4WD with a hard differential lock, or a lower gear. As you can see, here you can find references to all of the above all-wheel drive systems.

Some front wheel drive cars may have a driving rear axle. A small electric motor is mounted in the main gear housing, which is connected at the request of the driver - the e-4WD system. The electric motor is powered by car generator... Such a system improves vehicle handling on the track in a rainstorm, and also helps to confidently navigate snow-covered, icy and muddy sections of the track. A striking representative of cars with this system is latest models BMW.

Subscribe to our feeds in

Among car enthusiasts, disputes do not subside as to which is better - front, rear or all-wheel drive. Everyone brings up their arguments, but does not admit the evidence of their opponents. And in reality, determining the best drive option among the three options available is not easy. This requires a detailed analysis and focus on the features of each of the drives. We must not forget that the drive is an important parameter of any vehicle, which must be taken into account when choosing. And each customer must personally decide for himself which drive is right for him. And for this you need to understand the difference between the systems and know their key differences.

Choice of car drive: front, rear or full.

Comparison criteria

To determine the difference between front-wheel drive and rear-wheel drive, and also to compare them with full, you should focus on some distinctive features. Everyone has heard, but not everyone knows what exactly front, rear or all-wheel drive means. The drive determines to which wheels of the vehicle the thrust from the power unit will be transmitted. All modern passenger cars have 4 wheels. Two are located in front, and two more behind. The power generated by the engine can only go to two or all four wheels. To understand the difference between front, rear and all-wheel drive, let's first give them a brief definition. This way you will know which cars are RWD, FWD and AWD.

Front wheel drive. Here, the thrust from the engine goes only to a pair of wheels located in the front of the car. A pair of wheels clings to the road and pulls the vehicle along. Together with this, a pair of rear wheels simply rolls by inertia.
Rear wheel drive. Here, all the power from the power unit goes only for a couple. When rotating, the wheels grab onto the ground, which makes it possible to push off the surface and ride.
Four-wheel drive. Distinctive feature All-wheel drive is the transmission of torque to 4 wheels, that is, to 2 axles. This allows them all to rotate at the same time.

Practice has clearly shown that there is no need for a permanent all-wheel drive, and therefore engineers have developed systems that allow, if necessary, to transfer all power to 2 axles at once. To understand the significant differences between systems, you need to evaluate them according to several important criteria, which include:

safety;
patency;
overclocking.

Now let's see what each of the drives is capable of.

Safety

Here it is important to understand what is different front-wheel drive from the rear, as well as how much safer four-wheel drive cars are mono-drive. Cars do differ in terms of safety performance, but some nuances should be taken into account here. Namely:

It is much easier to drive front-wheel drive cars, it is difficult to specifically skid them, which is why front-wheel drive compares favorably with rear-wheel drive. If you are, then you should give preference to this option;
When a rear-wheel drive car skids, it is not difficult to return it to its normal trajectory. To do this, it is enough to release the gas. When they go into a skid on the front drive, it is already extremely problematic to correct the situation;
It is more difficult to provoke a skid in a front-wheel drive vehicle compared to a rear-wheel drive vehicle. But it is easier to get out of the skid precisely if there is rear drive;
For cars with rear-wheel drive, drifts are the norm, and therefore drivers are faced with this phenomenon on a regular basis. Roughly speaking, on a car with rear-wheel drive, it is immediately clear how dangerous the road is, and front-wheel drive hides this. But when the car skids, it takes a lot of skill to taxi;
Rear-wheel drive cars also skid without the ability to get out of the situation. This happens when the permissible speeds are exceeded. Then a simple gas discharge will not give results;
The situation with four-wheel drive cars is even more complicated. When driving on slippery road the behavior of a four-wheel drive vehicle may be similar to that of rear- and front-wheel drive vehicles. It all depends on which wheel the vehicle slipped on;
A car with front-wheel drive has very high rates of directional stability in comparison with rear-wheel drive;
If the road is muddy or snowy, the front axle works better, and the rear axle skids. If the gas pedal is not operated correctly, the rear-wheel drive car will quickly deploy in such conditions;
Four-wheel drive perfectly overcomes snow, mud and off-road conditions and copes with its tasks better than front-wheel drive counterparts. But in the absence of an interaxle differential in the design, the entrances to turns become more difficult;
Rear-wheel drive acceleration is faster, it goes into and out of skids easily. This makes rear wheel drive cars more fun to drive. Although in slippery conditions, the negative side of such a system opens up.

It cannot be said unequivocally that front, rear or all-wheel drive is better than others in terms of safety. It is important to consider how each of them works in different conditions. Working rear-wheel drive in its behavior is markedly different from the front and full. Each system must be able to use it correctly. And here the skill of the driver plays an important role. Although experts advise making a choice also based on the presence of the ESP system in the configuration, which is responsible for directional stability. The perfect assistant to simplify the task of operating a machine with any drive. ESP is able to effectively control the behavior of the car and correct errors that the driver makes.

Passability

Also, drivers are actively arguing about which drive is better - front, rear, or still full when it comes to cross-country ability. Here many will definitely give preference to all-wheel drive vehicles. But don't jump to conclusions. It should be understood what is the difference and differences between four-wheel drive, front-wheel drive and rear-wheel drive when it comes to the need to get out of a difficult road situation. Most often with them because of large snow drifts... There are several important arguments on this score:

The cross-country performance of front-wheel drive vehicles is slightly higher when compared with rear-wheel drive vehicles;
When the front axle is working, the wheels are pressed to the ground due to the engine mass, which helps to reduce the number of slippage;
The driving wheels of the front axle are steering, that is, the driver himself can set the direction of movement;
When the car slips, the front and four-wheel drive, due to the work of the front wheels, pulls the car, and the rear wheels simply follow the leading ones;
Rear-wheel drive cars behave worse in such situations. The back part is demolishing, and therefore it becomes extremely difficult to manage the process;
If you need to get out on a slippery slope, the front axle is objectively superior to the rear. Here the front wheels can slip, but they still continue to pull the vehicle. The rear wheels spin, skid and want to turn the car all the time;
The best in terms of climbing on slippery roads will be the four-wheel drive, which is able to climb to the top even without slipping. But you cannot rely entirely on the capabilities of the four drive wheels, since the capabilities of such systems are limited.

In terms of cross-country ability, the all-wheel drive car objectively wins, and the rear-wheel drive system is an obvious outsider. The front-wheel drive is somewhere in the middle, although it is closer to the rear rather than full. If your plans do not include off-road conquest, and you are going to operate the car only on asphalt, a rear-wheel drive car is fine. When you periodically have to leave asphalt roads, getting out into the field or light off-road, you will need at least front-wheel drive. And all four driving wheels will be needed in difficult road conditionswhere there is a lot of snow, mud, uneven areas, dangerous descents and ascents.

Overclocking

One of the objective advantages of rear-wheel drive is excellent acceleration of the car. If the asphalt is dry, then the rear axle performs better than the front in this parameter. At the moment of acceleration, the mass of the machine is transferred to the rear wheels, and the front wheels are unloaded. This explains the slippage that occurs during acceleration in front-wheel drive vehicles. Although here, both types of drive are ahead of the car, where all four wheels rotate simultaneously. But provided that its power is equal to or superior to that of the front-wheel drive and rear-wheel drive competitors.

Important characteristics

To make the comparison even more objective and understandable, several criteria must be taken into account. It is they who in many ways can tell the car enthusiast which car it is better for him to buy.

In terms of fuel consumption, the front-wheel drive car is the obvious favorite. It is more economical than rear-wheel drive versions by about 5-7%. And all-wheel drive cars take the last position, because they consume the most fuel;
Rear-wheel drive has no drive shafts in the front wheels. This increases the maximum steering angle and reduces the turning radius, which is a useful advantage in heavy traffic conditions;
Front-wheel drive production for car companies cheaper than rear-wheel drive vehicles, which makes these vehicles generally more affordable on the market. Availability has led to the growing popularity of front-wheel drive cars, which are produced significantly more than rear-wheel drive and all-wheel drive together;
A weighty argument in favor of the front drive wheels is handling on slippery roads. Such cars do not impose increased requirements on the level of the driver's skill, which cannot be said about the car, where the drive goes to the rear pair of wheels.

When choosing a new or used car with front or rear drive, most car enthusiasts will give preference to the first option. And there are a number of explanations and objective reasons for this. Such cars are affordable, economical, simpler and do not require much experience and special skills from the driver himself. It is worth buying a car with a rear-wheel drive system in a situation where you have great experience driving, and you want to enjoy this process. RWD is fun to drive. The sensations are markedly different from those observed when operating a front-wheel drive vehicle. But be prepared for certain challenges.

All-wheel drive options

More and more recently, buyers are giving preference to all-wheel drive vehicles. This can be explained by the gradual decrease in the cost of machines with a drive to all four wheels, as well as the variety of systems. You already know how four-wheel drive differs from the system front type... Now you need to understand the features of the all-wheel drive itself. To do this, you should study the variety of systems that are:

permanent;
manually connected;
connected automatically.

Each vehicle four-wheel drive system has its own distinctive features... Moreover, they are not as similar as they might seem at first glance. Let's analyze all the variations of the all-wheel drive separately.

Constant

Here, the four wheels of the vehicle are permanently connected to the power unit of the car, each of which grabs the roadway and helps to push the car forward. This is an important advantage for many driving situations. But in reality, permanent all-wheel drive manifests itself only if there is an additionally connected system for ensuring exchange rate stability. It helps to brake a specific wheel, preventing unwanted slippage. Cars with this type of permanent drive consume a lot of fuel, although there are back side in the form of increased reliability. If you plan to buy a car equipped with full permanent drive to conquer off-road conditions, be sure to make sure that there is a center and center differential lock. Otherwise, the result of passing difficult sections may openly disappoint you.

Manually pluggable

Many complain that the manually connected all-wheel drive system is very inconvenient and outdated. It really is. But if you look purely at the cross-country ability, then it is with such a drive that it is the highest. In normal day-to-day operation, the machines are rear-wheel drive. If necessary, the driver can manually connect the front wheels to work. But to do this, you first have to stop. It is pointless and even dangerous to operate the car when the front axle is constantly connected. In this mode, the load on the transfer case increases, and the activity of rubber wear increases. Another disadvantage of such a system is increased consumption fuel by car. And here it is not so important whether the driver connected the front axle or not. Although it cannot be said that manual all-wheel drive has no advantages. Such cars show themselves excellently in off-road conditions. Plus, the system itself is highly reliable.

Automatically pluggable

If you are looking for the most modern all-wheel drive system, which is characterized by excellent prospects, then you should opt for the automatically connected one here. The engineers themselves note that the system is not yet ideal, certain improvements and improvements are required. Therefore, it is better not to test the capabilities of such machines in serious off-road conditions. Car manufacturers have their own options for implementing an automatically connected type of all-wheel drive. But the principle is the same for everyone. It consists in the fact that one wheelset is connected to the engine on a permanent basis, and the second can independently be connected when the need arises. Multi-plate clutches are used for connection. The electronics are responsible for the automatic activation of the second pair of wheels. Therefore, in normal operation, the car is rear-wheel drive or front-wheel drive, depending on the specific car model. And when the electronics understands that the conditions are becoming more difficult, it is difficult for the car to overcome obstacles with only two wheels, the second pair is connected.

The key advantage of the auto-connect system is cost-effectiveness and ease of use. There is no need to make stops and connect the wheels. Computer in automatic mode connects a second pair of wheels when there is a real need to switch to a more passable all-wheel drive. But we must not forget that the reliability of the multi-plate clutch is not as impressive as that of the classic manual all-wheel drive system. Automation will be the best solution for overcoming urban snow drifts, slippery slopes and light and medium off-road conditions. But when driving into difficult conditions, it is better not to experiment, because here the automatic drive to all four wheels is not yet showing its best side.

Advantages and disadvantages

If we simplify as much as possible all the conclusions drawn earlier, then we can say that the best car drive is complete, supplemented by a system of exchange rate stability. But these machines are expensive and expensive to maintain. Plus, don't forget about active fuel consumption. If you want to become the owner of an economical and easier to operate machine, then yours is definitely the best choice will be front-wheel drive. According to all its characteristics, such a car will be the best choice for a beginner and an experienced driver, who value reliability, confidence and an optimal combination of price and quality. But rear-wheel drive cars are only suitable experienced driverswhose purpose is to enjoy driving. Considering all these factors, certain conclusions can be drawn regarding the strengths and weaknesses of each type of drive. Let's start with front-wheel drive vehicles. Their main advantages include:

low market value;
efficiency (low fuel consumption);
better cross-country ability cars versus rear-wheel drive competitors;
good directional stability when driving on slippery road sections.

Such cars do not have any serious drawbacks. As for rear-wheel drive cars, there are such advantages:

better overclocking;
good exit from drifts;
lack of slippage at the start.

The disadvantages include poor adaptation to operation outside of an asphalt road. In winter, driving such a car is extremely difficult. Especially if necessary, drive into a hill on a slippery area. Their price is slightly higher, and they consume a little more fuel than front-wheel drive competitors. All-wheel drive has its strengths and weak sides... The benefits include:

excellent overclocking;
increased cross-country ability.

But from the shortcomings they distinguish high consumption fuel, increased market value, and expensive service and repair. Here, everyone can draw their own conclusions for themselves. It is difficult to define an objective leader because there are different assessment criteria.

So motorists themselves have their own characteristics, on which they base their own choice of vehicle. Efficiency and ease of management are important to one, so front-wheel drive will be the best choice for them. Others want new sensations, and therefore a rear-wheel drive car would be the best solution. Don't forget about all-wheel drive vehicles, having different versions, their strengths and weaknesses. Each drive wins in some way, but loses to competitors in some respects. Build on what you expect from the car. This will be the starting point for you to select the most suitable drive type.

The best prices and conditions for the purchase of new cars

Credit 6.5% / Installment / Trade-in / 98% of approvals / Gifts in the salon

Mas Motors

The type of vehicle drive is determined depending on which wheels are leading in the transmission design. There are three main configurations: rear-wheel drive, front-wheel drive and all-wheel drive. The design decision of the engineers plays an important role in the control concept and influences the dynamics of the machine as well as other characteristics. The first cars were equipped exclusively with rear chain driven when placing the motor in the center. Machines with longitudinal installed motor, Checkpoint, cardan shaft and the leading rear axle, but the complexity of the design gave rise to the search for engineers for more simplified implementation schemes.

Comparison of cars with rear and front wheel drive.

The advent of front-wheel drive cars marks a new milestone in the evolution of the automotive industry. The ease of execution led to lower production costs, and in the fifties and sixties, front-wheel drive cars became widespread. Ease of control, compactness, relatively low cost of cars, in which the torque is transmitted to the front wheels, ensured wide popularity of such models.

Disputes about which type of drive is still better do not subside today, but it is impossible to come to a common opinion due to the relevance of the advantages of each of the design solutions, depending on the operating conditions. Despite the worldwide popularization of front-wheel drive models and their many advantages, the leading automakers BMW, Mercedes and other equally respected concerns do not depart from the classic performance realized through a rear-wheel drive scheme, which says a lot. It is almost impossible to notice the difference in handling on flat city roads, but all the advantages and disadvantages can be felt under certain conditions.

Advances in equipment equalize RWD and FWD cars with. The modern equipment of machines that meet the reliability parameters allows minimizing the risks of loss of control in emergency situations, but here the driver's experience and composure play a dominant role. Virtuosos of counter-emergency driving are able to keep any car on the road, regardless of the type of drive and the number of options.

Rear drive

The design of the transmission of a car with rear wheel drive (RWD) ensures the transfer of torque from the engine to the rear wheels, which are leading, due to them the movement is carried out. It's impossible to say unequivocally what is better - a rear-wheel drive or a front-wheel drive car - is impossible. When choosing a model, it is necessary to take into account the nature of the operation and the driving skills of the motorist. When accelerating, the weight of the car is transferred to the rear axle, loading the rear drive wheels and unloading the front ones, as a result of which traction is improved, engine power is used more efficiently, and the wheels skid less.

The rear-wheel drive device provides a variety of engine positions. The transmission includes a clutch, gearbox, differential, axle shafts, cardan and final drives. A front-wheel drive car does not have such a number of system elements, is famous for its ease of control with minimal driving skills and is more affordable than it also differs from a rear-wheel drive one. Moreover, when buying a car executive class or racing, the choice of the classic design option will be relevant.

RWD Benefits:

good dynamics of acceleration of the car;
the behavior of a rear-wheel drive car is more predictable, drifts occur at a lower speed than that of a front-wheel drive;
getting out of a skid on a car with RWD is much easier: it is corrected by throttle release (as opposed to front-wheel drive) or by turning the steering wheel towards the skid while holding the clutch, braking in this case is unacceptable;
less vibrations from the power unit are transmitted to the steering wheel;
the maximum steering angles are larger and the turning radius is smaller. The front wheels set the direction, while the rear wheels, to which the engine power is transmitted, push the car. This is due to the ease of entering turns, confident ascent;
the ability to use different control techniques, including controlled skidding, which is not feasible for a car with front-wheel drive;
uniform tire wear;
the implementation of the drive can be with a very different arrangement of the motor and other transmission elements;
ease of access to the units for maintenance due to their even distribution.

Rear wheel drive disadvantages:

the production of cars with RWD is more expensive, as a result of which the final price tag is also higher, budget models are equipped with front-wheel drive;
increased total weight of the car due to the greater number of structural elements;
with any layout, the interior space is stolen (by a cardan tunnel or a motor);
larger;
the complexity of the rear axle design, the need to monitor the condition of the bridge and timely maintenance;
the likelihood of burrowing in snow or mud is higher.

Front-wheel drive

The main difference between rear-wheel drive and front-wheel drive vehicles lies in the design of the components and assemblies. The torque generated by the engine is transmitted to the front wheels, thereby achieving good road holding. Front-wheel drive (FWD) cars are lighter and more compact, and assembly is simpler and cheaper, which is why most automakers produce models in this design. Thanks to the accumulation of units in one place, it was possible to achieve an increased interior space. In cars with FWD, all transmission elements are united by one unit, the gearbox also includes main gear with a differential, and the front wheel drive shafts come out of the gearbox housing.

The design difference implies a completely different principle of machine control. If skidding is a common thing for rear-wheel drive cars, then you need to try to get a front-wheel drive car skidded. However, this is the danger, since poor grip during icy conditions is not so noticeable for the driver, and it is much more difficult to get away from a skid on the front drive. Drivers who have switched from a "classic" to a front-wheel drive car often make the mistake of trying to align themselves without considering the physical properties of the structure.

The principle of behavior in the event of a skid is radically different. On the front-wheel drive, you cannot slow down, or rather, on the contrary, you need to increase the gas and maintain the speed until the trajectory of the car stabilizes, in contrast to the rear-wheel drive, where you need to release the gas. Intuitively, the driver releases the pedal, but here it is necessary to take into account the features of the transmission, following the rules for driving a car with different types drive. Parking on a front-wheel drive car is much more convenient, because the drive wheels turn in the direction of the turn, which allows you to set a clear direction. Cross-country ability due to the increased load on the front wheels is better than that of rear-wheel drive cars.

Front-wheel drive advantages:

cars are cheaper to assemble, respectively, the price will please the end consumer;
due to the fact that the driving wheels are also steering wheels, while slip is reduced due to the pressure of the engine weight on the front wheels;
stable course on slippery road surfaces;
a car with FWD rises better on a slippery slope: the front wheels, despite slipping, drag the car when you turn the steering wheel and press the gas pedal, the rear-wheel drive car will deploy with such maneuvers;
ease of management, convenient parking;
the car is more difficult to skid, but at the same time it is also more difficult to get out of it;
interior space due to compactness engine compartment and the absence of a propeller shaft;
less weight, compactness of the car;
economical fuel consumption.

Cons of front wheel drive systems:

tangible vibrations in the cabin, especially when equipped with a diesel engine;
during acceleration, reactive forces are transmitted to the steering wheel, it begins to tremble;
larger turning radius;
the machine has less maneuverability;
lack of proportional weight distribution due to the accumulation of aggregates in the front;
when skidding, it is more difficult to hold the car; to align, it will take considerable skill of the driver;
drifting on a front-wheel drive car will not work.

As a conclusion

When choosing a car, it is necessary to take into account the driving experience and operating conditions, it is impossible to specify which car is better - rear-wheel drive or front-wheel drive - despite the fact that the advantages of one type are manifested in the disadvantages of another. For beginners, it is better to choose a front wheel drive car, it will also good optionif you are planning outings on a dirt road outside the city.

Rear-wheel drive cars are more suitable for drivers with good driving skills, will be interesting to drive, and will also provide an opportunity to have fun through controlled drifts... In winter, RWD models require attention from the motorist, but this does not mean that they are less safe than front-wheel drive models with stable stability and handling parameters. Subject to car equipment anti-slip system ESP, on studded tires, it will be equally successful to climb slippery slopes with any type of drive.

If you buy a bolivar for practical reasons, the best front-wheel drive car, more affordable and economical. Rear-wheel drive cars accelerate well, easily enter a skid, but also get out of it without problems. In terms of cross-country ability, front-wheel drive cars are better, but you should not get out off-road with either RWD or FWD. So, cars with different types of drive have their own advantages and disadvantages, depending on the nature of driving, driving experience motorist and expected operating conditions.

Off-road driving is not applicable with any of these transmission designs. For this there is a separate class of cars - off-road vehicles equipped with all-wheel drive, where all wheels are leading. Permanent, manually or automatically connected all-wheel drive provides better cross-country ability, but cars of this type are quite "voracious", so when choosing it is important to consider models that correspond to the expected operating conditions.

The best prices and conditions for the purchase of new cars

Credit 6.5% / Installment / Trade-in / 98% of approvals / Gifts in the salon

Mas Motors

When buying a car, one of the decisive moments is the choice of drive. Which is better: front, back or full? Almost every car enthusiast will answer that four-wheel drive is cool, if you buy a car, then you need to give preference to him.

But the answer will not be so unambiguous if we consider all the advantages and disadvantages of each type. In addition, four-wheel drive can be plug-in. Maybe it is worth choosing it as the most successful alternative. But he also has many nuances.

How to choose? What are the points to be guided by when buying a car with a particular type of drive? How not to make a mistake, so as not to bite your elbows later? To answer all these questions, you should familiarize yourself with each species in as much detail as possible.

What's better

The choice of front or rear wheel drive for your car is the most important decision, which will subsequently play a significant role in the quality of control, how you will behave in extreme situations, in how you will generally drive. Few people know, but foreign driving schools have two training courses for future drivers. This is the control of front wheel drive and rear wheel drive vehicles. This is due to the fact that the concept of managing them is completely different.

To understand what the main differences are between cars with front and rear wheel drive, you should consider the diagram of both mechanisms in a little more detail. This will help you decide which drive is best: front or rear.

How rear-wheel drive cars work

Initially, all cars had this type of drive. In this case, the leading axle is the rear axle, which is supplied with torque from the engine.

The unit in such vehicles has longitudinal arrangement in the front of the car, that is, under the hood. The gearbox is connected to it. A cardan shaft goes from it, behind it - rear axlewhere the crankcase is installed, inside which the differential is located. The latter distributes the torque to both rear wheels.

The differential, in turn, is located between the two rear axle shafts. It is on them that the torque is distributed, and already from the axle shafts it is transmitted to the wheels.

The advantages of rear-wheel drive cars

disadvantages

The final price for rear wheel drive vehicles is higher. Therefore, most middle-class cars are produced with the front.
The usable space inside the vehicle is reduced, especially in the rear. The reason is the presence of a cardan tunnel inside the cabin.
In poor road conditions, the vehicle's passability is worse. But this claim can be challenged by the fact that neither front-wheel drive nor rear-wheel drive is suitable for off-road driving.

If you don't know which drive is better - full or rear, then they have a lot in common, so it will be quite difficult to choose.

Front-wheel drive car device

Later, cars with front-wheel drive appeared, which do not have half of the parts listed above in the chassis. The torque from the gearbox is transmitted directly to the front wheels. And at the back there is a regular axle, on the sides of which there are two wheels.

The first such cars began to be produced for widespread use in the thirties of the last century, and this step is considered progressive for the entire automotive industry. Such cars have become more affordable due to the savings in parts during production. A number of advantages over rear-wheel drive cars also play an important role in their popularization.

Benefits

The consumer price of such vehicles is significantly lower compared to rear-wheel drive vehicles, because the cost of additional parts and assembly is reduced.
The absence of a gimbal tunnel, which increases the comfort in the cabin.
Good directional stability, excellent cross-country ability on snowy roads and mud.
Front-wheel drive cars are significantly lighter than rear-wheel drive ones.

disadvantages

Features of cars with four-wheel drive

It is believed that all-wheel drive cars have collected all the advantages of front and rear wheel drive. And it is not surprising, because SUVs and crossovers are equipped with all-wheel drive, since they have to go through the most difficult roads without losing the level of comfort for the driver and passengers. But this type is also not devoid of disadvantages. Therefore, hardly anyone will have a question about whether four-wheel drive or front-wheel drive is better.

pros

increased cross-country ability in extreme road conditions;
with a sharp start, there is no wheel slip;
when driving, you can not pay attention to the condition of the road surface;
the dynamics of the car is significantly increased.

Minuses

Four-wheel drive cars have only two significant drawbacks:

high price compared to rear-wheel drive and front-wheel drive cars;
more complex handling.

But the first factor is justified increased cross-country ability, and the second is compensated by a sufficient level of professionalism of the driver.

Another controversial issue is the choice between permanent and plug-in drives.

Which is better - four-wheel drive or plug-in

Continuous drive advantages:

structural reliability;
with four-wheel drive, you can drive both on a normal road and off-road.

Disadvantages:

increase in vehicle weight;
high consumption fuel;
complexity of management;
decrease in controllability indicators.

Advantages of the connected drive:

ease of control on poor road surfaces;
cars with such a drive have a relatively small mass.

The only drawback is that it is impossible to drive on an all-wheel drive mode on smooth asphalt.

From all that has been said above, we can conclude that when choosing a car with one or another drive, you should be guided, first of all, by which roads you are mainly going to drive. Price is also not the last factor, because it will greatly depend on the drive system. In addition, do not forget about your level of driving skills and driving style.

Here is a video that will help you decide on the choice of drive for your car:

The number of all kinds of SUVs and crossovers on our roads is growing at a tremendous pace. One of the main advantages of such cars is the all-wheel drive system, the principle of which different models may differ significantly.

All types of all-wheel drive can be conditionally divided into three main ones: temporarily connected ( Part Time), constant (Full Time) and automatically connected (On Demand Full Time).

Temporarily connected four-wheel drive

Temporarily connected four-wheel drive, or as it is often called Part Time, does not allow for a long time to go in four-wheel drive mode. In this type of all-wheel drive, there is no center differential that would compensate for the difference in rotation speed of the front and rear axles. Without it, when driving on a dry road, transmission parts begin to wear out quickly.

All Wheel Drive Part Time can only be forcibly engaged to cross a difficult road section at low speed.

Usually a lever is used to connect transfer case transmission. Although in some versions, to connect the front axle, you need to get out of the car and turn special handles (hubs) on the front wheel hubs.

Only "full-fledged" off-road vehicles that are used for their intended purpose are equipped with a temporary all-wheel drive. Vivid representatives of such "crooks" can be called those who are in no hurry to hand over all-wheel drive control to electronic "brains".

In addition, almost all are equipped with "temporary" all-wheel drive chinese copies famous off-road vehicles of the 90s.

Real SUVs with Fair Part Time are slowly becoming history as they are supplanted by more modern all-wheel drive systems.

Permanent four-wheel drive

Permanent four-wheel drive, or FullTime, most manufacturers do not provide the ability to forcibly disconnect / connect one of the bridges.

Due to the presence of a center differential, such a transmission constantly (in any conditions) works in all-wheel drive mode. In addition, in modern models, the interaxle "diff" has its own electronic "brains".

With such a differential, the torque can be transmitted to the axles in different proportions, that is, not only 50/50. When a slip occurs, the "smart" differential can instantly "transfer" the torque not only to the axle with better grip, but even on a separate wheel that has something to catch on to.

This type of all-wheel drive is the most "advanced" among other 4x4 systems.

The abundance of "smart" electronics on the most modern systems allows the car to adapt even to a specific road surface (asphalt, gravel, sand, etc.), the driver only needs to press the desired button.

The most famous representatives of permanent all-wheel drive are the company with the proprietary Quattro system, and Subaru with the AWD (All Wheel Drive) system.

It is interesting that this type of transmission is equipped with completely "off-road" sedans, coupes and hatchbacks. This underlines the versatility of this all-wheel drive system.

Automatic all wheel drive

The automatically connected four-wheel drive (On Demand Full Time) allows the car to remain front-wheel drive and only in case of slipping of the driving wheels it connects the rear axle. Automatic connection of all-wheel drive in modern systems occurs almost instantly at the first sign of slipping.

Depending on the capabilities of a particular system, the torque between the axles can be redistributed in any proportion (from 10/90 to 90/10).

At the same time, the electronic stability control (ESP) allows you to maintain control over the car, which can suddenly turn from front-wheel drive to rear-wheel drive, and vice versa.

To overcome a particularly difficult road section, this type of drive (in most versions) makes it possible to forcibly redistribute the "floating" torque between the axles in a 50/50 ratio. Usually for this there is a button labeled 50/50, Lock, etc. But upon reaching a certain speed (40-50 km / h), the blocking will be disabled and the system will return to "floating mode".

In addition, a car with automatic all-wheel drive can be turned into a pure front-wheel drive, without any connections. Again using the "magic" button (2WD, etc.). Disabling all-wheel drive helps save fuel, and the need for four-wheel drive in the city does not arise often.

The automatic all-wheel drive is the “youngest” 4x4 system.

The vast majority of crossovers in our market are equipped with it. You can even say that such a drive is an essential attribute of a true crossover. The new type of car required a new type of all-wheel drive, everything is logical.

Which drive is full her?

It is quite difficult to determine which all-wheel drive is the most optimal, since each of them has its own advantages and disadvantages.

On serious off-road terrain, SUVs with a temporarily connected all-wheel drive and rigid mechanical locks of all differentials (center and cross-axle) will feel best. But in urban conditions, such machines do not give any pleasure from driving.

In turn, purely urban crossovers with their automatically connected all-wheel drive are practically helpless on any off-road, but they are controlled like ordinary cars.

The golden mean is a permanent all-wheel drive, which will master the off-road and will not give offense on the track.

But such a drive will not interfere with its work, that is, it may not be possible to save fuel or drive through a very difficult section (despite the "very smart" electronics).