
4WD for a sedan refers to four-wheel drive. Some four-wheel-drive sedans include the A4L, Audi A6L, BMW 5 Series, BMW 3 Series, Mercedes-Benz E-Class, Cadillac CT6, and Volkswagen Phideon. Taking the 2021 BMW 320I as an example, it is a mid-sized 4-door, 5-seater sedan with body dimensions of 4719 mm in length, 1827 mm in width, and 1459 mm in height, a wheelbase of 2851 mm, and a fuel tank capacity of 59 liters. The 2021 BMW 320I is equipped with a 2.0T turbocharged engine, delivering a maximum power of 115 kW and a maximum torque of 250 Nm. It features a double-joint spring strut front suspension and a multi-link independent rear suspension.

The term '4WD' for sedans refers to a four-wheel-drive system. Most traditional sedans are two-wheel drive, with either the front wheels pulling or the rear wheels pushing, but a 4WD system allows all wheels to work together. This design is particularly useful in rainy or snowy conditions, as all four wheels gripping the ground reduces the likelihood of skidding or slipping. Nowadays, advanced sedans use increasingly sophisticated 4WD technology, with some systems capable of automatically distributing power—for example, providing more force to the outer wheels during turns and saving fuel during straight-line driving. However, 4WD systems add weight and increase fuel consumption, and their advantages might not be noticeable during regular city driving. But when tackling mountain roads or making emergency lane changes, the added stability is well worth it.

Simply put, 4WD in sedans is a system where all four wheels receive power output. It distributes the engine's power to the front and rear axles through a central differential, preventing certain wheels from spinning or slipping on wet surfaces. This system is particularly useful on icy and snowy roads in northern regions. I used to struggle for a long time to start on icy slopes with a two-wheel-drive car, but with a four-wheel-drive sedan, it climbs steadily without any hassle. It's important to note that there are different types of 4WD systems: full-time 4WD is always active, on-demand 4WD usually operates in two-wheel drive and automatically switches to four-wheel drive when slipping occurs, while part-time 4WD requires manual switching. For , pay attention to the differential oil replacement cycle, as long-term neglect can affect power distribution efficiency.

4WD in sedans stands for four-wheel drive. Nowadays, many sports sedans are equipped with this system, and the most noticeable feeling when driving is the exceptional road grip, especially during fast cornering or emergency braking, as all four wheels work simultaneously to prevent the car from losing control. Compared to the four-wheel drive in off-road vehicles, which is purely designed for escaping tough situations, the four-wheel drive in sedans focuses more on enhancing handling and safety. However, it adds components like the driveshaft, increasing the car's weight by about 100 kilograms, and fuel consumption is slightly higher than the same model with two-wheel drive. If you frequently drive on highways or live in rainy areas, spending the extra money is quite worthwhile.

A sedan with 4WD indicates it has a four-wheel drive design. In principle, the power is distributed to all four wheels through the transmission system, with the greatest advantage being improved tire traction. In mountainous cities like where I live, this feature is particularly necessary. During winter snowfalls, my neighbors with front-wheel drive cars always have to install snow chains, while my 4WD sedan can handle it with regular snow tires. For daily use, it's important to ensure even tire wear; it's best to perform a wheel alignment every 10,000 kilometers, otherwise, it might affect the accuracy of power distribution. Additionally, the cost of the 4WD system is slightly higher, such as changing the transfer case oil every 60,000 kilometers, but it offers stronger driving safety in return.

In simple terms, a 4WD sedan is a car where all four wheels can be driven. Compared to traditional two-wheel drive vehicles, it has additional components like a transfer case and front-wheel drive shafts. I think the most practical scenario is driving uphill on a rainy overpass—two-wheel drive cars can easily skid when encountering standing water, but four-wheel drive cars provide stable power to each wheel, eliminating that worry. Nowadays, technologies like Audi's quattro or BMW's xDrive are mature and can automatically adjust the front-to-rear power distribution based on road conditions. Of course, there are obvious drawbacks: a four-wheel drive sedan with the same displacement consumes about 1 liter more fuel per 100 kilometers than a two-wheel drive car, and the heavier body also affects acceleration performance.


