What is Rear Wheel Drive?
Rear-wheel drive (RWD) is a form of engine and transmission layout used in motor vehicles, where the engine drives the rear wheels only. Until the late 20th century, rear-wheel drive was the most common configuration for cars. Most rear-wheel drive vehicles feature a longitudinally-mounted engine at the front of the car.
Rear-wheel drive (RWD) means that the power from the engine is delivered to the rear wheels and the rear wheels push the car forward. The front wheels do not receive any power and are free to manoeuvre the vehicle. The weight of an RWD vehicle being more evenly spread than an FWD vehicle, creates a better balance of weight.
This is why most sports cars such as the Corvette and Camaro are RWD and are more exciting to drive. The disadvantage of an RWD vehicle is that they do not perform well in poor weather conditions such as rain or snow because they are more prone to loss of traction on slick roads.
Vehicles that feature rear-wheel drive are a bit more complicated. Power is transferred from the transmission to the rear wheels through a long driveshaft to a differential. RWD vehicles handle much better than front-wheel drive vehicles and you will notice the difference in curves, turns, and when navigating through traffic situations. Traction won’t be as good, especially in wet or snowy road conditions.
Rear-wheel drive vehicles are better for towing because the front wheels have better steering without a ton of weight on them. Plus, with the power transfer and the tongue weight of the trailer, the rear of the vehicle squats, which gives the rear wheels more traction. If you get stuck, adding weight over the rear wheels may help.
Rear-wheel drive vehicles sometimes feature 4×4. When you put the vehicle into 4×4, the vehicle will get power to all four wheels as needed.
How Does a Rear-Wheel Drive Work?
The most common setup in rear-wheel drive vehicles involves having the engine at the front of the car connected to a driveshaft that sends power to the rear of the car. This arrangement dominated cars built in the twentieth century for several reasons:
- Body-on-frame vehicles have more space under the vehicle because of the frame rails, making it more practical to run a driveshaft under the vehicle for power. Most modern cars are not body-on-frame and generally have a lighter unibody design with a lower center of gravity.
- As mentioned above, the rear wheels handling all of the power with the front wheels handling all of the steerings is straightforward, meaning it was cheaper to manufacture and simpler to service.
- The engine at the front of the vehicle put something substantial in front of the driver and passengers if the vehicle hit something head-on.
Performance vehicles often use rear-wheel drive for consistent and sharp handling. In mid-mounted and rear-mounted engine vehicles, power usually goes to the rear wheels to save weight and put the heavy engine over the driven wheels for better traction.
The fact that rear-wheel drive has been used for so long means the technology has improved dramatically over the years. Issues like oversteer (the rear of the vehicle losing traction in a turn) and poor traction in slick conditions are less frequent in modern rear-wheel vehicles.
What vehicles use the rear-wheel drive?
- Large sedans and family cars: While many large cars and vans use front-wheel drive or all-wheel drive, many sedans and wagons mid-size and larger come in rear-wheel drive.
- Trucks and SUVs: Most body-on-frame trucks and SUVs use rear-wheel drive as standard. Most will have an option for a four-wheel drive. Commercial trucks and vans use rear-wheel drive as well.
- Sports and performance cars: Many car enthusiasts still prefer rear-wheel-drive vehicles for their handling characteristics and power delivery.
Advantages of Rear-Wheel Drive
- During dry conditions, rear-wheel-drive improves handling due to “load transfer” in acceleration and more even weight distribution.
- Rear-wheel drive tends to have less costly maintenance since there aren’t as many parts packed into a small space. Front-wheel drive repairs and maintenance may cost more since they have to remove more parts for workable access.
- You won’t experience “torque steer,” the tendency that FWD vehicles have to veer to the right or left during acceleration.
- Towing large loads is easier since the wheels doing the pulling are located closer to the load. Also, steering is much easier since the back wheels are providing the power while the front wheels do the work of steering.
- While drifting is not recommended for most drivers, it is easier to drift with RWD than FWD or 4WD/AWD.
Disadvantages of Rear-Wheel Drive
- The rear-wheel drive may be more fun to drive, but it also makes it more difficult to master. With modern stability and traction controls, however, the driving differences of RWD don’t present a problem for most drivers.
- There is less interior space due to more room needed for the transmission tunnel and driveshaft.
- There may be less trunk room since more equipment must be placed underneath the trunk.
- The driveshaft, which connects the front engine to the back axle, adds more weight. RWD weighs slightly more than FWD, but less than 4WD and AWD.
- Additional materials translate to a slightly higher purchase price.
- Since RWD pushes the car rather than pulls it, it has more difficulty maneuvering in wet and snowy conditions. With modern technology, such as stability and traction control, however, this disadvantage is greatly reduced.
