Difference Between 4WD, AWD, RWD, and FWD in Chicago, IL

What constitutes a drivetrain, and does the selected configuration really matter? Why do people prefer a drivetrain that is RWD for performance vehicles and AWD in difficult terrain? Our drivetrain experts have laid out the drivetrain differences to help you determine which you want for your new Nissan car, SUV, or pickup.

What is a Drivetrain?

The drivetrain is a cluster of components that transfers engine torque to the wheels to propel a car forward. Components include the transmission, differential, drive shaft, and axle. FWD vehicles have a part called a transaxle that combines the transmission and differential into one unit attached to a half-shaft. AWD and 4WD vehicles have an extra component called a transfer case.

The differential is the part that distributes power to individual wheels. Depending on the drive type, only the front wheels will receive power, only the rear wheels, or all four wheels. The differential can also cause one wheel to spin faster than the others, such as the outside wheel when making a turn. Limited slip or locking differentials won’t do this, keeping each wheel aligned instead.

Front-Wheel Drive

An easy way to tell which drivetrain you have is to assess when you step on the gas, does your car feel like it’s being pushed or pulled forward? If your vehicle feels as though it is being pulled along, then your car is front-wheel drive. In a front-wheel-drive car, the engine, transmission, differential, and driven wheels are all up front, and the rear wheels are pulled along. This is the most popular configuration in modern cars.

Advantages

• All the major components are housed upfront, so the passenger and cargo compartments are bigger.
• Front-wheel drive systems are light and better on fuel economy than the other options.
• The weight of the engine over the driven wheels gives front-wheel drive vehicles great traction.

Disadvantages

• All the major components are squeezed into a small area, making service and repairs more difficult.
• The nose-heavy configuration puts increased wear on the front tires and suspension.
• Front-wheel drive cars are harder to control under heavy acceleration because the nose-heavy configuration weighs down the front wheels.

Rear-Wheel Drive

When you step on the gas, if your car feels like it’s being pushed forward rather than pulled, you have a rear-wheel-drive set-up. This system runs from front to back, and that power is sent to the back wheels and the front wheels steer. Once the most common drive type, it’s now typically only found on sports cars and heavy-duty vehicles.

Advantages

• Rear-wheel drive systems cars distribute weight more evenly across the front and rear. Better balance means more precise handling, especially when cornering or with high-horsepower engines.
• Because rear-wheel drive is a simpler and more robust design, it requires less servicing and is easier to fix when repairs are needed.

Disadvantages

• Rear-wheel drive systems occupy more room, so rear-wheel-drive cars often have less passenger and cargo space than front-wheel-drive cars.
• Because there is less weight over the driven wheels, rear-wheel-drive cars can’t get as much traction and have more difficulty driving in rain or snow.

All-Wheel Drive

The all-wheel drive creates propulsion through all four tires, thanks to a centrally positioned differential. Torque distribution is adjusted to enhance traction automatically without driver intervention. After front-wheel drive, this is the second most common drive type. It’s mostly found on crossovers and sport/luxury sedans.

Advantages

• All-wheel drive improves handling on dry roads.
• All-wheel drive improves traction on wet/snowy roads.

Disadvantages

• All-wheel drive systems are bulky and can greatly reduce fuel economy.
• All-wheel drive systems are complicated and are often more expensive to fix.

Four-Wheel Drive

For functional purposes, 4WD is comparable to AWD. Unlike AWD, 4WD is usually part-time, and the driver has the option to turn it on when they want it. Additionally, 4WD uses limited-slip or locking differentials so that the front and rear wheels always receive the same amount of power. Four-wheel drive is mostly found on trucks and large SUVs, vehicles that are capable of towing and hauling large amounts of weight.