AWD vs 4WD vs 2WD - Whats the Difference?

 


A car's drivetrain, which is the system of parts that connect the engine to the wheels to make a vehicle move, can be set up in different ways which greatly affect a vehicles performance and capabilities on the road. These three different configurations are known as two-wheel drive, four-wheel drive, and all-wheel drive.

Many are still confused about the major distinctions between these systems because some can seem quite similar, but it is important to note their mechanical and capability differences. So lets break it down!



What Is Two-Wheel Drive? (2WD)

 
As the name suggests, 2WD vehicles are those that have power directed into only two of of the wheels. This is either done through the rear wheels, a rear-wheel drive system, or the front to create a front-wheel drive system.

Front-Wheel Drive (FWD)
Directs power and momentum the the front tires; isolating the rear tires. This means that the engine and transmission sit completely atop the front axle and is used to "pull" the rear weight of the car. Because this is the cheapest type of drivetrain to design, it is the most commonly installed in vehicles. Often cars will have FWD base models and more expensive options will offer other types of systems.

What Are The Pros Of FWD?
  • Cheap design and installation saves money for consumers
  • Solid gas mileage due to less weight
  • Better traction because of weight distribution
What Are The Cons Of FWD?
  • "Nose-heavy" weight distribution leads to worse handling - especially at high speeds
  • Not optimal for driving in poor weather conditions - although better than RWD



Rear-Wheel Drive (RWD)
Directs power and momentum to the rear tires - essentially "pushing" the car from the back. This is the oldest drivetrain layout which distributes its weight more evenly over the front and back of a vehicle, which has many different implications for performance and capabilities. This type of system is more commonly found high-performance vehicles as well as trucks that plan to pull heavy loads.

What Are The Pros Of RWD?
  • More agile and responsive handling due to a more even weight distribution - taking pressure off of the front tires
  • Load bearing capabilities thanks to weight added on the rear tires
  • Solid design offers more durability which takes less damage

What Are The Cons Of RWD?
  • Very poor handling in rain or snow due to less traction
  • Typically less cargo and passenger room

 

What Is Four-Wheel Drive? (4WD)


Four-wheel drive, often referred to as 4x4 or four-by-four, is a system commonly installed in trucks, SUVs, and other vehicles that are meant for off-roading. The transmission will apply power to all 4 tires equally - perfect for low-traction terrain that might be uneven or easy to get stuck in. Through sending an equal amount of power to each wheel, a vehicle will be more prepared for many more situations which may need to utilize the front tires, rear tires, or a combination of both.

4WD can be turned on and off with the switch of a button - alternating between 2WD and 4WD.

What Are The Pros Of 4WD?
  • Perfect for those who enjoy off-roading through rugged terrain with improved traction
  • More power capable of pulling very heavy loads
  • Can be turned off and on allowing for more versatility in performance and MPG

What Are The Cons Of 4WD?
  • More expensive than 2WD vehicles - in MSRP, maintenance, and fuel costs
  • Should NOT be turned on when driving on dry flat pavement - high risk of damaging your drive train in sharp turns


What Is All-Wheel Drive? (AWD)

Similar to 4WD, an AWD drivetrain system supplies power to all four wheels at once. It does not do so equally however, due to its computerized system that detects which wheels need more or less power depending on traction and driving angles. For example; a car that is making a sharp turn will give more power to the outside wheel which needs to cover more area than the inside wheel.

AWD is always on thanks to the computerized detection system which adapts to situations.

What Are The Pros Of AWD?
  • Adapts to a variety of different surfaces and terrains to offer excellent traction
  • Automatically senses road conditions - requiring no input from the driver
  • Works well at all speeds when 4WD is only recommended at low speeds

What Are The Cons Of AWD?
  • More expensive than 2WD vehicles - in MSRP, maintenance, and fuel costs
  • Not as effective in extreme terrain off-roading compared to 4WD

What Is The Difference Between AWD and 4WD?

Many people use the terms all-wheel drive and four-wheel drive interchangeably because they are very similar, however this is not completely correct. While both of these drivetrain systems distribute power to all 4 wheels, there are important distinctions between the two that affect vehicle performance.

  • AWD automatically detects road conditions and makes power distribution adjustments itself while 4WD must be turned on manually
  • AWD power distribution to the tires is constantly changing while 4WD is always equal - allowing for smoother handling for AWD
  • AWD vehicles can be driven on most terrain while 4WD is only recommended for off-roading