Is 4H High-Speed Four-Wheel Drive or Low-Speed Four-Wheel Drive?
1 Answers
2H is two-wheel drive, 4H is high-speed four-wheel drive, and 4L is low-speed four-wheel drive. The difference between 4L and 4H lies in the change in the vehicle's gear ratio. Compared to the low rotation speed of the wheels, the engine requires a higher rotation speed, which means the small gear drives the large gear, resulting in increased torque applied to the wheels. Part-time four-wheel drive distributes power to all four wheels through a transfer case, allowing switching between 2H, 4H, and 4L via a four-wheel drive lever or electronic button. Dry paved roads do not require four-wheel drive, so selecting two-wheel drive (2H) is sufficient. Part-time four-wheel drive should not use 4H or 4L on dry paved roads, whether driving straight or turning. Most off-road vehicles can handle general rough roads with their high ground clearance, but encountering off-road conditions or severe weather changes the situation. When driving on snow, 4H is suitable. Using 4L may result in excessive torque, causing the wheels to slip and the vehicle to get stuck. Even on snowy paved roads, 4H provides better traction for the wheels. 4H has broader applications and is typically used on surfaces where 2H two-wheel drive might cause slipping. Additionally, engaging 4H makes it easier for the vehicle to climb hills. The same applies to driving on muddy terrain—most situations do not require the high torque output of 4L, as it can cause the wheels to spin in place and get stuck. Of course, off-road vehicles in 2H mode can handle many loose or slippery gravel and dirt roads, but activating 4H ensures more stable and smoother driving.