What is the Difference Between Part-Time 4WD and Full-Time 4WD?
1 Answers
Part-time 4WD has only two driving modes, namely two-wheel drive or four-wheel drive. Full-time 4WD means all four wheels always have driving force, providing an all-weather four-wheel drive mode. The specific differences are as follows: 1. Part-time 4WD is equipped with a robust dog clutch-style differential lock between the wheels, enabling 100% "rigid" locking (when not locked, it functions like a standard open differential). In four-wheel drive mode, both the wheel-to-wheel and axle-to-axle connections are rigid, with fixed overall speed and torque output between the front and rear axles, forming a rigid linkage. 2. Since both the front and rear axles are rigidly connected, they must rotate at the same speed. Therefore, part-time 4WD relies on wheel slippage to absorb speed differences during turns, with sharper turns making this more noticeable. On surfaces with excellent traction, turning becomes impossible (as the wheels do not slip), meaning part-time 4WD cannot operate smoothly on high-traction roads. 3. Full-time 4WD, as the name suggests, ensures all four wheels always have driving power. Not only does it feature the commonly known open differential between the wheels, but it also requires a center differential between the front and rear axles. With power distributed to all four wheels, full-time 4WD vehicles exhibit superior traction and handling.
