What type of 4WD system is AWD?

[Reagan]

AWD (All-Wheel Drive) is a full-time four-wheel drive system. Full-time four-wheel drive means that both the front and rear wheels of the vehicle have power, and the engine's output torque can be distributed in different proportions to all wheels based on the road conditions to improve the vehicle's driving capability. Four-wheel drive modes can be divided into full-time four-wheel drive and part-time four-wheel drive. The difference between them is that part-time four-wheel drive can switch between 4WD and 2WD, while full-time four-wheel drive is almost always in 4WD mode. Four-wheel drive systems are categorized as follows: 1. Full-time four-wheel drive: The vehicle is always driven by all four wheels independently; 2. Part-time four-wheel drive: The driver can manually engage or disengage the transfer case to switch between two-wheel drive and four-wheel drive based on road conditions; 3. On-demand four-wheel drive: The system automatically switches between 2WD and 4WD based on driving conditions, engaging four-wheel drive only when necessary and remaining in two-wheel drive otherwise.

[StEloise]

I often encounter slippery roads when driving myself, and it's thanks to the AWD (All-Wheel Drive) system that I've never had an accident. AWD means all four wheels are constantly being driven, unlike part-time 4WD which only engages when slippage occurs. It uses a center differential and sensors to dynamically distribute power between the front and rear wheels—for example, providing more power to the outer wheels during cornering, or automatically balancing power between front and rear wheels when climbing snowy slopes. The biggest advantage of this system is its all-weather stability: no slipping when hydroplaning through standing water at high speeds in rain, and no rolling back when climbing snowy inclines. However, the downsides are also notable—complex structure leading to expensive maintenance, and fuel consumption about 10% higher than two-wheel-drive vehicles. If your area frequently gets snow, choosing an SUV with AWD is definitely the right move.

[OTanner]

I've studied various 4WD systems, and AWD is actually the general term for full-time four-wheel drive. Its biggest difference from part-time 4WD is that it can be used on paved roads for extended periods without damaging the drivetrain. For example, Audi's quattro and Subaru's Symmetrical AWD are typical representatives, which automatically adjust the torque distribution between the front and rear axles through multi-plate clutch differentials. The most intuitive feeling when driving daily is the stability during cornering, especially when taking hairpin turns quickly on mountain roads—the car feels like it's glued to the ground. However, it's important to note that tuning varies significantly between brands, with some being more front-wheel-drive biased and others more rear-wheel-drive biased. For modifications, I recommend getting a set of winter tires; AWD paired with winter tires can improve traction on ice by 30%.

[Jacob]

AWD stands for all-wheel drive, which I understand as a supervisor that never takes a day off. All four wheels are constantly engaged, with sensors monitoring speed differences between them every second. The best part about driving it in the city is the no-slip starts on rainy days—it feels rock-solid when you hit the gas at a green light. Once, I drove a friend's part-time AWD car and clearly felt the rear wheels slip for half a second before the system kicked in on a wet ramp. However, AWD systems are quite delicate; mechanics say the differential fluid must be changed every 60,000 km, or the multi-plate clutch can overheat. Nowadays, many EVs also feature electronically controlled AWD, with independent front and rear motors delivering faster response times.