The drive wheel debate will obviously never end. If so, we will bring our “five kopecks” into the heated discussion about Which drive is better and which one to choose ?
Trying to isolate the “good, real” and “bad, wrong” drive types are tantamount to controversy about the taste of tomatoes and bananas. Each scheme is optimal for its platform, affects the handling of the car, determines the understeer, the nature and characteristics of sliding, forms the method of withdrawing the vehicle from a skid, and also leaves a huge imprint on maneuverability. However, there are always pros and cons in one way or another.
The engine is longitudinally at the front, the drive wheels at the rear (thrust is transmitted by means of a propeller shaft) – this is an automobile classic. Currently, the lion’s share of cars is built on front-wheel drive platforms, and chassis with rear-wheel drive are the diocese of purebred sports cars and, as a rule, premium brand products, regardless of segmentation.
For example, the BMW 3 Series
and Mercedes-Benz C-Class throughout their history have consistently distinguished themselves with a classic powertrain layout.
Rear-wheel drive allows for optimal axle weight distribution and efficient use of engine power.
When accelerating, the weight is redistributed and the rear axle is reloaded, helping the tires better cling to the road surface.
Acceleration is not accompanied by the effect of power steering, as is the case with front-wheel drive vehicles, since the steering wheel is not connected to the drive wheels.
On the asphalt, the “classic” can bring a lot of pleasure to the experienced driver and allows you to use different methods of control, from drift (power sliding) to the circuit style with the construction of the trajectory of cornering. In bends, the owners of the classic layout demonstrate neutral understeer, as is the case with BMW, or slightly understeer when the car seeks to straighten the trajectory in a corner.
As for the disadvantages of cars with rear drive wheels, here it should be noted an earlier breakdown into a skid and worse cross-country ability in comparison with front-wheel drive vehicles. Another thing is that the slips are corrected on an instinctive level – it is enough to release the accelerator and turn the steering wheel towards the skid, without touching the brake pedal, and without being late with the corrective actions of the steering wheel.
Otherwise, a rhythmic drift will begin with a constantly increasing amplitude, which will ultimately end in a U-turn.
In addition, the scheme forces the use of a propeller shaft and, accordingly, a tunnel that invades the interior space.
Currently, most passenger cars and crossovers have a chassis with front drive wheels and a transverse arrangement of the power unit (thrust is transmitted to the steered axle through drive shafts).
These are such popular models as Volkswagen Golf and Tiguan
, Skoda Octavia
, Toyota Camry and RAV4 , numerous Peugeot , Renault and Citroen… However, history is also known for a front-wheel drive layout with a longitudinal arrangement of the engine, which, for example, can boast of “Moskvich-2141”.
One of the main advantages of the average front-wheel drive, which is especially pronounced during UK operation, is good cross-country ability on snow and stability of movement on slippery surfaces.
This feature is due to the additional axle loading by the power unit and the bogie effect.
Imagine that a person who actually plays the role of driving wheels drags her along – in this case, additional stabilization and steering are not required.
The downside of front-wheel drive technology is the tendency to understeer.
For an ordinary driver, moving within a speed limit under the vigilant control of electronic active safety assistants and common sense, this is not a problem.
True, if a skid suddenly begins, then you should not let go of the gas pedal, but continue to press it, that is, resort to actions that contradict instincts.
We especially note that it is highly desirable for every motorist to comprehend the subtleties of the handling of his car and simulate emergency situations in safe conditions.
Another problem is the limitations on the transmission and sale of power. Under intense acceleration, the front of the car is unloaded, the wheels lose their “grip”, and in “athletic” vehicles, at the same time, the effect of torque steering occurs, when the driving wheels are pulled to the side, and the steering wheel literally breaks out of the hands.
Nonetheless, hot hatchbacks in the B and C size class are mostly front-wheel drive and still provide the pilot with a lot of fun and excitement.
The manufacturers took control of torque steering with improved MacPherson strut front suspension with steering knuckles and reduced roll-in shoulder.
The transverse layout is not well suited for large aggregates.
At one time, the Americans put huge “eights” on models with front drive wheels, but the distribution of weight along the axles and handling of such land yachts, of course, was not the same as that of hot hatches.
Finally, from the point of view of operation, front-wheel drive is not always convenient – for example, on engines with a V-shaped scheme, it is not always convenient to change the spark plugs on the half-block near the engine shield.
Not all motorists correctly assess the purpose of the all-wheel drive transmission and believe in its ability to change the laws of physics. For example, sometimes we hear opinions that cars with AWD or 4WD nameplates do not require winter tires.
Recall that the all-wheel drive system is helpful on slippery surfaces and off-road conditions, but is not able to stop vehicles – the brakes and tires are responsible for this for the season.
To call one type of all-wheel drive good and the other bad, in our opinion, is wrong.
It all depends on the car on which it is installed and its area of application.
For an ordinary crossover that does not have off-road or sporting ambitions, the widely used scheme with the selection of traction to the rear axle by means of a multi-plate clutch is quite suitable.
This is the difference between Volkswagen Tiguan, Renault Duster, Mazda CX-5 .
When operating, do not forget about the possible wide limits on the transmission of torque to each axle and, accordingly, the variability of controllability.
On rough terrain, one should take into account the peculiarity of the electronic imitation of cross-wheel locks (if any) – sometimes it helps quite sluggishly.
Permanent all-wheel drive with center differential (Toyota Land Cruiser Prado, Land Cruiser 200, Mitsubishi Pajero Sport) also does not require additional manipulations from the driver – at most, activate a downshift and engage differential locks, if any.
It should also be remembered that getting a full-time machine out of a drift requires stable counter-emergency skills.
The simplest version of the all-wheel drive with a rigid non-differential front axle connection (aka part time) allows you to drive in rear-wheel drive mode and save fuel.
The main drawback of the system, typical, for example, for the UAZ Patriot, Jeep Wrangler and Toyota Hilux, is the natural limitation on operation with the front axle connected. Moving on a dry surface or a surface where there is no mutual slipping of the wheels threatens with increased loads on the transmission and the failure of its elements. Usually this feature is not liked by average users who want to have control over the situation in any traffic situation. However, part time in most cases is used on specialized off-road vehicles, which are purchased for completely specific tasks by not random people.