If you are planning to buy an SUV, you might have to choose between models with a four-wheel-drive (4WD) or all-wheel-drive (AWD) drivetrain. Many people are often confused between the two. Here, we have tried to provide information about AWD vehicles that will clear the confusion.
The Difference Between 4WD and AWD Vehicles
In 4WD, there are two differentials and a transfer case. The 4WD drivetrain directs power to the transfer case that further distributes the power to the front and rear axles to drive the wheels. In 4WD, the front and rear wheels receive almost the same power.
In some 4WD vehicles, the 4WD mode is temporary or automatic. In most driving scenarios, the 4WD system works as a two-wheel drive, powering only two wheels (front or rear). Only when the driver activates the 4Wd mode will the system direct power to both front and rear axles.
In AWD vehicles, there are three differentials: front, rear and central. The AWD drivetrain directs power to all four wheels in all conditions. However, when slip is detected, there could be a variable difference in power directed to each wheel. For example, if one of the wheels is slipping, the AWD system may direct more power to that specific wheel to improve traction.
Now let’s look at some important facts about all-wheel-drive vehicles.
AWD Vehicles Are Not Fuel Efficient
If you are looking for a car with good fuel economy, an AWD vehicle is not the right vehicle for you. The AWD drivetrain provides power to all four wheels all the time. The result is that the engine has to burn more fuel to generate the power needed to drive all four wheels. Also, AWD vehicles weigh more, adding to fuel consumption.
Types of Tire Matter
If you are living in a region where snow falls for many months of the year, you need to buy winter tires for an AWD vehicle. Without winter tires, an AWD vehicle will not offer good traction and you will only feel driving a heavy vehicle with a false sense of security.
Size and Tread Depth of Tires Are Important
All four wheels of AWD vehicle need to have the same size and model of tires, from the same manufacturer. This is important because there can be a considerable difference between the tires of the same size from different manufacturers. The tread depth tolerance of AWD vehicle is around 3/32 of an inch across all four tires.
If the tread depth difference is more, it will affect the circumference of the tire. If there is a major difference in tread depth and circumference of the tire, the wheel with smaller tire circumference would have to rotate faster than other tires, which will damage the vehicle’s transmission.
Now that you have more knowledge about AWD vehicles, you can decide whether one is the right car for you.