Can the Prado h4f and h4l be switched at will while driving?
3 Answers
The Prado h4f and h4l can be switched while driving, but it is not recommended to do so arbitrarily. Characteristics of four-wheel drive: A manual transfer case is installed behind the transmission, and a component called the drive axle is installed on each of the front and rear axles. The torque output from the transmission is transmitted to the drive axles on the front and rear axles through the transfer case and drive shaft, and then the torque is transmitted to the wheels through the drive axles. Internal design of four-wheel drive: The four-wheel drive system is a full-time type, equipped with a viscous coupling, eliminating the need for a manual transfer case, and automatically distributing torque to the front and rear wheels as needed. On normal road surfaces, the four-wheel drive system distributes 92% of the engine's output torque to the front wheels and 8% to the rear wheels; on slippery road surfaces, at least 40% of the engine's output torque is distributed to the rear wheels. When the front wheels begin to slip, the speed difference between the front and rear wheels will cause the viscous fluid in the coupling to immediately thicken and lock the coupling, so that the drive shaft only transmits torque to the rear wheels.
When driving a Prado, I often switch between these modes, but you can't freely switch between H4F and H4L while moving. Especially at high speeds, like above 80 km/h, switching can damage the drivetrain, potentially causing gear grinding or uneven wear. It's best to operate at low speeds, such as below 20 km/h, or when completely stopped. H4F is the normal 4WD free state, suitable for city driving; H4L, when locked, is better for off-road or slippery conditions, but sudden switching on dry roads can cause jerking or even loss of control. Last time I switched hastily in the rain, I almost skidded—now I only dare to switch after slowing down. Remember to check the manual; older Prado models might require turning a small lever when switching, so steady operation is key—don’t take risks to save time. Avoid frequent switching during daily driving, and maintain the differential oil properly for durability.
As a car enthusiast, I find the H4F and H4L design of the Prado quite clever, but you shouldn't switch recklessly at high speeds. Shifting while driving can easily damage the transmission because H4L lock forces the wheels to rotate synchronously, and switching at high speed causes loud gear clashes. I've tried switching at a slow speed of 30km/h, which was fine, but I wouldn't recommend doing it above 40km/h. It's better to slow down or stop and follow the manual's instructions for operating the lever or button. The main reason is to prevent premature wear of drivetrain components or sudden torque changes that could lead to unstable handling. If I frequently go off-road, I switch to H4L before setting off; for city driving, I keep it in H4F. By the way, excessive tire wear can also mislead the effectiveness of mode switching, so regular checks on tire pressure and differential maintenance are essential.
