Rear-wheel drive car: description, device, pluses and minuses

At the moment there are cars with different types of drives. It is front, full and rear. When choosing a car, the future owner must know the features of each. Most professional drivers prefer to buy a rear-wheel drive car. What are its features? We will talk about this in our article.

Characteristic

Rear-wheel drive means the presence of a classic layout and placement of units. The engine and the box are arranged longitudinally. This is the simplest scheme. Therefore, the first cars were with rear-wheel drive. But recently there has been a trend towards a front-wheel drive. It is considered more technological. But such manufacturers as "BMW", "Mercedes" and others, still do not abandon the "obsolete" layout.

Device

The rear-wheel-drive vehicle does not have a transverse engine arrangement. Here we use a simplified scheme. First comes the engine, then the box, the driveshaft and the bridge with the differential. In contrast, the front rear-wheel drive car has a more even weight distribution. Unlike the "technological" analogs, here the mass is not concentrated at one point. Hence the more correct distribution of mass and load.

The main nodes are:

• Cardan shaft.
• Rear axle with differential.

Let's look at the features of each element.

Cardan shaft

It is a steel rod of cylindrical shape. Through the crossings this shaft is attached to the gearbox. On the other hand, the mechanism is connected to the rear axle. The cardan shaft under the body is located. If it is a car, a special tunnel is placed for its placement. This is to ensure that the metal rod is not deformed to stones and asphalt. Cardan gear is very reliable. However, the main problems concern crosses. They constantly fail. And it does not matter which brand was produced rear-wheel drive car. The only exception is the SHRUS connections. For the first time they were used on the "Niva". However, the Ulyanovsk Kozlik (UAZ 469) is still using crossings as the main connection.

Rear axle

In its case there is a differential. It is located in the middle of the bridge. It is this mechanism that receives the torque from the cardan gear. In the differential of the rear axle, the axle shafts are integrated. They reliably connect to the wheels. When the propeller shaft rotates, it drives the differential. The latter, in turn, rotates the wheels through the semiaxis. Also note that the transmission fluid is used inside the rear axle to lubricate the differential and semi-axle gears. To ensure that it does not leak, the design provides an oil seal. On some cars, the rear axle is also recessed into the body so that the mechanism is less damaged. However, because of this, the space in the cabin and the trunk considerably decreases. But why then are still produced rear-wheel drive cars of the brand "BMW", "Infiniti" and so on? There are reasons for this. Let's look at the advantages of this type of drive.

pros

The first plus is the free space under the hood. Its rear-drive cars are much more because of the uniform arrangement of the elements. On the front drive, all the assemblies are assembled in the engine compartment. This makes it difficult to maintain the car. The next plus is the correct weighting. Due to this, we get a uniform load on the front and rear axles. Also, this type of drive transfers fewer vibrations to the steering wheel and the body itself. The car perfectly obeys the steering wheel. If desired, you can enter the managed drift. The rear axle of the rear-wheel drive car will not be anything. If you let go of the gas, the machine again aligns and will continue to move. It is the rear drive that is suitable for drifting. The driving load is carried out on the rear axle, and the front performs only the control function. From the transmission and other components you will not hear any vibrations, as it happens on some cars with front-wheel drive. The next plus is maneuverability. In the design there are no CV joints on the front wheels, and therefore the turning angle is much larger. This is very useful when driving in traffic or during parking. The angle of turning on such cars is 15 percent more than on front-wheel drive cars. Also note the high maintainability. Service here is much cheaper. Not surprisingly, commercial vehicles are still equipped with this type of drive.

Acceleration Dynamics

We will pay special attention to this aspect. On such machines more dynamic overclocking. If you "go too far" with gas, then at the start you can get a rear wheel drive car. At this time the car body goes back. Based on the laws of physics, the load on the rear axle increases. As a result, the wheels get a bigger hook. The machine does not grind, as it is on the front drive. And no matter what engine power - the result will be approximately the same. Therefore, in drag-racing only cars with rear-wheel drive are used.

disadvantages

The design assumes the presence of many additional nodes. This cardan, bridge, differential, semi-axle. While it is sufficient to apply the hinge of equal angular velocities to transmit the torque on the front drive . Therefore, the price of such cars is slightly higher. The next is the presence of liquids. The differential uses about two liters of transmission oil. It should be changed every 30 thousand kilometers. In the joint, the lubricant is filled for the entire service life. It is required to closely monitor the condition of the stuffing boxes. If there is a bridge, this is very bad. At a low level of lubrication, the teeth of the differential wear out more strongly. And the cost of a new bridge, even for domestic UAZ, is not less than 40 thousand rubles. Another drawback is the presence of protrusions in the passenger compartment for the propeller shaft and the rear axle.

About patency

In terms of snow-covered roads or mud rear drive significantly loses. Wheels push the car from behind. As a result, he "digs" himself a snow trap. The car starts to bury. Therefore, on cars with increased cross-country capacity, it is used (no, not anterior), but a four-wheel drive. However, due to the presence of two bridges and a transfer case, the construction becomes much more complicated. This entails an expensive repair of assemblies and units. But from the point of view of patency, he is the leader.

What cars are rear-wheel drive?

As we said earlier, now this arrangement is done only on expensive cars. These are the German BMW and Mercedes, Jaguar, Infiniti, Maybach, as well as some Japanese cars Toyota and Nissan. Among the domestic is the "Volga" and the classic models of the VAZ. And of course, all commercial equipment. Budget cars with this type of drive now do not produce.

Conclusion

So, we found out the features of the rear drive. Despite the popularity of the competing front, it still remains relevant. This is especially true for commercial vehicles. After all, there is a frame construction here. And to make ledges under the bridge and cardan there is simply no sense - the road clearance of the truck allows to use them and without additional tunnels.