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AWD, 4WD, 4×4 ZR found the four-wheel drive. The answer will surprise you

Versed with the abbreviations that manufacturers mark their AWD models.Kolodochkin Michael “at the wheel”Expert

“AWD compared to 4WD gives less torque”.

The opinion of one Internet “expert”

The abundance of clever abbreviations type AWD, 4WD and Part-Time 4WD, Full Time 4WD, 4×4, 4matic, and other abbreviations is a good publicity stunt, inspiring the owner of the car that are not wrong when buying a car, choosing a “best”. At the same time, unfortunately, these labels often do not have unambiguous interpretation. Who does not believe can type in the search box, say, AWD and 4WD — you’re in such a jungle, from which you can not get out. About technical literacy is generally better not to stutter.

Meanwhile, by and large, the main types of machines, called four wheel drive cars, or three (if deeply get into those thickets “Haldensee”, single-ended, differentials, etc.). Typical representatives of the “Trinity” is shown in the photo below.

UAZ Patriot. The drive to the rear axle is constant. The drive to the front axle — connected; there is no center differential.UAZ Patriot. The drive to the rear axle is constant. The drive to the front axle — connected; there is no center differential.

Lada 4×4. The drive to both axles — constant, there is a center differential.Lada 4×4. The drive to both axles — constant, there is a center differential.

The Renault Duster. The drive to the front axle — constant. The drive to the rear — plug through the coupling. (Known inverse pattern when the main drive shaft is the rear, and a coupling connects the front…)Renault Duster. The drive to the front axle — constant. The drive to the rear — plug through the coupling. (Known inverse pattern when the main drive shaft is the rear, and a coupling connects the front…)

And here’s the first feature for many — unexpected. From the point of view of a pedant of the title of all-wheel drive vehicle from the specified Trinity truly worthy only of the Tolyatti car! After all, she’s only four-wheel drive works in 100% of cases, while for others it is, in General, the plug-in function: car is frequently riding in mode, rear-wheel drive cars, and the Duster — like front-wheel drive VAZ “eight”.

The second feature is also fun — there are few people realize. Even at the disconnected axles (front on “UAZ” and back to Duster) a bunch of transmission parts, these vehicles still are constantly rotating! UAZ will spin the axle shaft of the front axle and driveshaft, Duster — rear gearbox and drives the rear wheels, and cardan. And this is the noise and fuel consumption even in monoprinter mode.

Now — the most cunning: as these cars are allocated points. Consider a few situations. While conventionally the friction and other losses are absent, the load on the wheels is the same, the longitudinal and transverse weight distribution is uniform, and the adhesion of the tire and coating the same, if no other reservations.

Car driving on flat road in a circle

UAZ Patriot. If the front axle is not connected, the torques on the rear wheels is distributed evenly, and the front points do not exist. If to connect the front axle, on each axis, points are divided equally, but the distribution between axles will depend on the loads and forces of adhesion. On dry pavement this will cause the front and rear wheels will begin to slip relative to each other as their moments to equalize nobody: center differential do not.

Lada 4×4. If the center differential is not locked, the torques at all four wheels are equal. Accordingly, no slippage will not. If you lock the center differential, as on the Oise, when driving on a good road in the rotation appear relative slippage of front and rear wheels.

The Renault Duster. When driving in the Lock mode coupler rigidly connects the rear axle, which can lead to slippage on a good surface.

Driving wheel hanging in the air

UAZ Patriot. If the front axle is not connected, the machine will stop. When you connect the bridge all the time from the engine will get “nezavisla” axis, and the machine will go further.

Lada 4×4. With the differential unlocked the machine will stop. If you lock the center differential, it will go further.

The Renault Duster. In selector lever position 2WD vehicle. In the Auto position or Lock the clutch connects the rear axle and it will move.

Truths

  • Symmetric differential always aligns the moments: the centre on axes transverse — on wheels.
  • Blocked cross-axle differential actually turns the axle in the analogue of the pair of wheels of a railroad car. Even so, the moment still raised wheel is equal to zero.
  • Posted on the wheel moment is always zero, regardless of the presence or absence of differentials.

What’s in a name?

And where are all these other AWD and 4WD. Calling a colleague on the automobile — he, to my delight, it confirms what I come up with myself. Allegedly, these signs generally are technically not legislative, but purely marketing, conventional. Therefore, there may be exceptions. But basically AWD is a “monoprinting”, who have the ability to connect a second drive axle. And 4WD is, say, a machine with a permanently attached axles with the given initially, the distribution of torque between the axles (for example, 50 to 50, who have the ability to lock the center differential).

In General, if you only need from time to time to get out of the snow, any of these schemes with a hint of polnoprivodnyj significantly superior to the common “4 by 2”. And the majority need just that. Well, those who are preparing for a real off-road feats, you still live in a parallel universe, and therefore any explanation is not needed.

Good luck on all the roads!

AWD, 4WD, 4×4 ZR found the four-wheel drive. The answer will surprise you

  • We regularly ask the question, how many sets of snow chains you need to buy for four-wheel drive vehicle and a number of bracelets for a car need. The answer is simple — it does not matter, four-wheel drive the car or not. Enough of one set of chains (2 PCs) on the same axle. With regards to bracelets, the more of them installed, the better “rowing” the car, the less wear each bracelet. The recommended amount is 6 pieces

AWD, 4WD, 4×4 ZR found the four-wheel drive. The answer will surprise you

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