Front, rear, all-wheel drive - differences and selection criteria

To be more precise, there are four types of drive. These are front, rear, full and torque transmission to all wheels, if available. car more than two axles. It is not entirely correct to say that one drive is better. Each transmission type has its own advantages and disadvantages related to the quality of the road surface, driving style, the purpose of the car and other factors. All this should be examined in more detail.

Front-wheel drive

It is used in most cars produced since the 90s by the global auto industry. This is due to a number of positive qualities of such a transmission, one of which is the compact placement of all its components. The power unit, gearbox, drive - everything is actually located in one place. As a result, the usable area used to accommodate passengers and luggage remains unoccupied in the car. There are other benefits too:

• ✅ installing the engine across the car (this is typical for most front-wheel drive cars) makes it possible to transmit torque "directly", which involves fewer parts
  
• ✅ the pressure of the power unit on the drive wheels provides better traction, which is important if it is difficult or slippery
  
• ✅ FWD cars are easier to design with fewer components, resulting in a cheaper vehicle
  

However, there are also negative sides and they are enough. First of all, it is worth noting the skid: in a rear-wheel drive car, the driver begins to slow down to get out of it - a completely natural human reaction to danger. If the drive wheels are front, to align the car, you must do the opposite, that is, press on the gas. And this is unnatural for an inexperienced driver: how can it be a danger, and you need to speed up the movement!



The second negative point is the accelerated wear of the brake mechanisms. This is due to the fact that the bulk of the car with front-wheel drive (up to 70%) is under the hood. The exception is luxury and sports cars, where the so-called. weight distribution. In ordinary cars, during an emergency stop, the front brake pads receive an enormous load and wear out faster than the rear ones by about 2-3 times. The result is a more expensive service.

Rear drive

In this case, the power unit is installed along the car body, and the torque is transmitted to the wheels through the cardan shaft. At first, cars were made exclusively rear-wheel drive: the mechanics of that time had a very vague idea of ​​​​how to make the wheels drive, and even turn. The main advantage of rear-wheel drive vehicles lies in its performance. During acceleration, the inertia transfers the bulk of the machine back, which reduces the likelihood of slipping. That is why such well-known brands of sports cars as Ferrari, Lamborgini and others have rear-wheel drive. The same can be said about VIP-cars, such as Mercedes S-class, BMW of the third series. There are other advantages:

• ✅ rear-wheel drive allows you to evenly distribute the load between all wheels, which is associated with the placement of heavy components along the entire length of the machine (box, cardan shaft, rear axle)
  
• ✅ rotation is made at a larger angle with a smaller radius
  
• ✅ cars with the described transmission are easier to get out of a skid (in dry weather): just release the gas pedal
  

And now for the cons. The most unpleasant is the need to equip the tunnel in the cabin, which eats up space for passengers. True, for expensive and voluminous models this is insignificant. The second minus is a serious risk of skidding in bad weather: rain, snow, when the rear axle is not loaded, that is, there are no passengers or luggage. However, modern systems such as ESP (if installed) solve this problem. And another drawback is the loss of engine power when cornering. This is due to the “pushing” of the car with the rear wheels forward.

Four-wheel drive

Transfers the power of the power unit to 4 wheels, which provides good grip on the road surface and stability when entering a turn at speed. Four-wheel drive is divided into 3 varieties.

Adaptive system

It is installed on cars of sports and family type, crossovers, full SUVs, sometimes minivans. The adaptive drive automatically distributes the power of the power unit between the wheels as needed. Initially, 100% of the torque is transferred to the front axle. In the event of loss of traction, part of the power goes to the rear wheels.

Plug-in drive

The simplest option, used, for example, on UAZ and Niva. From foreign cars - Jeep Wrangler or Ford F150. The transfer case is involved in the transmission of torque, connecting the front axle with the manual movement of the corresponding lever in the cabin. In normal mode, the car moves with the rear axle connected to the engine.

Permanent four-wheel drive

This implies a mode when 4 wheels all the time receive torque from the engine and it is impossible to disconnect one or another axle from it. Such a system is rare today: except perhaps on some models of specialized equipment.

Advantages and disadvantages of all-wheel drive

The main plus is patency. If all wheels are driven, the stability of the car improves when performing maneuvers, especially on slippery roads. The downside is the complexity of the design, which increases the cost of the machine due to the presence of a center differential, a transfer case. Accordingly, maintenance costs will be higher. In addition, compared to other types of transmissions, there is more fuel consumption here, all 4 tires wear out at once. In vehicles with two driving wheels, the service life ends first for those to which torque is transmitted.

With which transmission to choose a car?

Front wheel drive cars are the most common. This is due to lower maintenance costs, relatively low fuel consumption, and the absence of a tunnel in the cabin, which is important for compact cars like Fiat Uno. Also, a vehicle with a leading “front end” is appropriate in mountainous areas - it will climb more confidently on a steep slope, even if it rains or the road is covered with ice. Rear-wheel drive is installed on some budget commercial vehicles (for example, in cheap GAZelle configurations). It is also present on many prestigious VIP cars. If you are a fan of off-road travel or live in a region where heavy snowfalls and rains are not uncommon, choose a 4WD car.