What is the difference between full-time 4WD and 4WD? This is still a difficult question, as these two types seem to be similar but in fact they are different.
Simply, full-time four-wheel-drive systems generally operate on clutches, while four-wheel-drive systems use a differential locking mechanical connection. In fact, the AWD four-wheel drive system can always work well on both high friction and low friction surfaces. 4WD has better mechanical strength but because it works by mechanical differential lock, you should not run the car but always leave the differential in the locked state. If you drive a car, especially a 4-wheel drive high-speed pickup truck on a large friction road, do not ask why you often have to replace the front sprocket!
The new Ford F150 Raptor is a special pickup that features both AWD and 4WD. This model is equipped with a Terrain Management System with a 2-mode transfer case: a full-time four-wheel-drive mode with clutch and a micro-lock mode differential to provide outstanding off-road capability.
Tony Greco, F150 Raptor Project Leader, said, “The new Raptor features the benefits of a full-time four-wheel drive system such as optimum traction when it’s raining or snowing, muddy road, excellent gravel thanks to electronic differential lock “.
All the great capabilities of the Ford F150 Raptor are controlled through the Terrain Management System. When traveling in urban areas, the driver can choose 4×4 Auto mode – based on the operating conditions of the vehicle, the system will automatically select the clutch or differential lock to transmit the torque to the vehicle.The driver can also select the exact weather for the vehicle to maximize its performance or choose a sport steering mode – the TMS system will transmit a lot of torque to the rear axle to deliver the cover.
On off-road, the driver can select Mud / Cat mode to activate only part-time wheel drive. In addition, the Rock Crawl mode will activate 4×4 low bridge mode to conquer large boulders. In any mode, the driver can also intervene to make the most accurate decisions on his / her own depending on the vehicle’s operating environment.