How 4 Wheel Drive Vehicles Work


DrivetrainDespite the numerous online resources all touching on cars, it remains a fact that car shopping is still a headache. The number of trucks, cars, and SUVs in which all the wheels get power from the engine has grown on a significant scale since the 1980s. The rise in 4 wheel drives means two-wheel drive systems sold to customers is not enough.

The primary distinction of 4 wheel drive system is that the vehicles ate typically used and build to handle the unpaved wilderness. In most cases, four-wheel drive vehicles are designed and intended for off-road application. Audi Quattro proved the effectiveness of four-wheel drive cars. Since then, there have been lots of enhancements on these drive systems


How Four Wheel Drive Systems Work

Modern four-wheel drive systems have become very complex due to infusion with electronic control technology. Vehicles are driving on 4WD offer an assurance of safety and security both on and off-road. Such cars have improved towing and hauling capabilities for people and equipment. The emphasis of 4WD vehicles has been shifting from mere traction enhancements to on-road safety and handling capabilities.

Three main components define 4WD systems. These are the Engine, The Transmission, and the Transfer Case. Modern vehicles come with engines that are typically fuel injected and then controlled by an electronic control unit. The ignition spark control allows the system to control the engine power in small ranges but with quicker response times. As far as transmission is concerned, with manual transmission, the control is left with the driver while electronically controlled ones, control is integrated into traction and torque.

Vehicle Dynamics

Depending on the nature of torque transfer, we can have three sub-models of 4WD. These are the Part-time mode, full-time mode, on-demand mode. The primary motive forces on the vehicle are applied to the tire patches that are in contact with the road surface. The contact load and friction limit the total maximum friction force at the tire patch. 4WD systems are all about traction control. The ideal drivetrain allows the driver to propel the vehicle in the intended direction and speed, in a manner that promoted the ease and ability to maintain control.

The only active external forces on the vehicle come from the tire patches. The sole option of the driver is to control or influence the tire patch. Traction control comes in to improve the mobility of the vehicle at low speeds. In difficult terrain, the system works at improving the tractive performance as well as improving safety and handling at higher speeds due to directional stability.

There are different tactics used in traction control. First is power management. Most modern engines and automatic transmissions are electronically controlled and may be adapted and integrated into traction and the stability control systems. There are also brake based the traction and stability control systems based on the principle of selectively applying the individual wheel brakes to achieve slip reduction. Lastly, we have yaw control, where yaw motion defines the rotation of the vehicle about the vertical axis.

Leave a Reply

Your email address will not be published. Required fields are marked *