Is All Wheel Drive the Same as 4 Wheel Drive?
There are so many types of engines, car makes, and models, several types of transmission systems, and different drivetrains to choose from when buying a car. One thing that confuses car buyers is the difference between AWD and 4WD.
These two terms seem interchangeable for people buying cars the first time. So, are they the same? And what does 4×4 mean?
Is All Wheel Drive The Same As 4 Wheel Drive?
No. These are two different drivetrains with the 4 wheel drive being optimized for off-road driving and the all wheel drive delivering power to both the front and rear wheels simultaneously.
All-wheel drive is ideal for on-road use. It delivers more power to all the wheels at the same time, making the vehicle more powerful than front wheel or rear wheel models. Four-wheel drive is an off-road drivetrain that delivers power to the wheels equally. When you drive on rugged terrain, all the wheels need equal power, especially in areas where traction is low.
There are many more differences between these two as I outline below:
AWD vs. 4WD: Where is Each Drivetrain Applied and What Does All Wheel Drive Mean?
All-wheel drive systems are ideal for SUVs and cars that drive on-road while four-wheel drive is for trucks and vehicles engineered to drive off the road.
In all wheel-drive system, all the four wheels receive power at the same time, but the amount of power each wheel receives might be different. Depending on the automaker, some AWD send more power to the front wheels while others send more power to the rear wheels. Performance cars send more power to the rear wheels, making them perform better in several conditions.
Modern all-wheel drive systems offer torque vectoring that allows them to distribute power to the wheels based on input from the driver and the road. Such vehicles offer enhanced handling capabilities. This increased handling capability makes all-wheel drive systems common in modern performance cars.
You will find several crossover SUVs and family cars with AWD systems, thanks to the affordability and ease of use of the AWD. The system is also light and has fewer complex parts.
If you have an off-road truck, it is highly likely that it runs a 4WD system. Off-road vehicles such as Jeep Wrangler are able to traverse rugged terrain. The 4WD system sends power to all four wheels equally so that the vehicle can navigate difficult terrain with ease.
When a truck needs to drive through a beaten path, the 4WD system comes in handy as every wheel can handle the terrain. 4WD models are available as part-time or full-time as discussed later on this guide.
The main feature in off-road trucks is the 4WD system. However, there are several other features that enable the truck to drive off the road. Some of these features include locking differentials and skid plates under the vehicle.
Locking differentials allow the driver to negotiate difficult terrain. You may not use them when driving on a regular path, but when you get on a beaten path, the differential allows you to climb over locks while driving at a very low speed.
Skid plates are common under the body of 4WD vehicles to protect them from stumps, rocks, and any other features on the rough terrains. Today, automakers even have additional automated features that adjust the drivability of a vehicle based on the nature of the terrain.
What is the Difference Between Part-Time and Full-Time AWD Systems?
The all wheel drive system delivers equal power to all the four wheels. This system is either full time or part time AWD. Full-time AWD continuously drives all the four wheels – this is ideal for fully off-road vehicle models such as Jeep Wrangler.
Part-time AWD, also known as automatic AWD, operates as two-wheel drive (2WD) most of the time, especially when you need to save on wheels. These models deliver power to all four wheels only when you need extra traction. For models that drive on the road most of the time, but partly off the road, part-time AWD system comes in handy.
Full-time AWD works great on dry pavement regardless of the terrain. When you drive on slippery grounds such as in snow or ice, the full time AWD deliver more traction to the wheels to allow the car to drive better. With such models, you have great handling all the time, giving you confidence when you need it.
Part-time AWD models will send power to two driven wheels – these can either be the front or the rear wheels, depending on the car model. The system will engage the two remaining wheels in case extra traction is needed.
The modern part-time AWD vehicles come fitted with sensors that send information to a computer that then regulates the amount of power that goes to the wheels.
What are the Differences Between Full-Time and Part-Time 4WD?
Full-time 4WD system sends power to all four wheels equally continuously while part-time 4WD systems operate as 2WD most of the time. The latter only switches to 4WD when the vehicle needs more traction.
4WD systems will likely come to mind when you think of vehicles that send power to all four wheels. However, these systems have drastically improved. Although the principle of these models is as old motorized transportation, they have seen several improvements to make them more versatile.
When you think of the 4WD vehicle, the picture that may come to mind is that of a large SUV or truck with 35-inch wheels. However, while the system is still primary in large trucks and SUVs, it is also common in smaller SUVs, crossovers, and even smaller cars that drive off the road.
The 4WD system uses front, rear, and center differentials to deliver power to all the wheels. This way, the vehicle operates at maximum traction under different conditions.
In part-time 4WD models, the vehicle drives by two wheels, which are mostly the rear wheels. When you drive such a car, you have the option to choose when to engage the other two wheels. Engaging the other two wheels requires the driver to either push a button or a lever.
In some models, the part-time 4WD system allows the driver to lock the differential when more traction is needed. This also happens in full-time 4WD models that may allow the driver to select how power shifts to the wheels, depending on the terrain of the area you drive.
Most 4WD systems offer low and high ranges that the driver can choose between. These models feature an electronic switch or a mechanical level that allows the driver to shift between the two ranges. You can shift to low-range when you need more traction while the high range acts as the default setting that helps you navigate slippery on-road conditions such as ice, snow, and loose gravel.
What are the Pros and Cons of AWD Systems?
One of the main advantages of AWD systems is that the driver doesn’t have to choose when to engage the drivetrain. If the system is full-time, the wheels will have power at the same time, depending on the needs. If the system is part-time, the system has sensors that determine when to engage or disengage the wheels.
All the driver has to do is drive and everything will be okay. This system is available in a wide selection of vehicles from compact sedans to performance vehicles.
The system will perform exemplary in several conditions, including snow and ice. You can also drive vehicles with these systems on a light off-roading trip. However, when you need to drive on really rugged terrain, the car will not perform as great as you need.
Serious off-roaders want to have the choice on when to engage or disengage the wheels. The system increases the cost of a vehicle and can also reduce its fuel economy.
What are the Pros and Cons of 4WD Models?
When you need to handle adverse conditions, a 4WD model comes in handy. The system is ideal for on-road and off-road vehicles. Today, the perception that 4WD is only in heavy duty trucks is fading as more luxury SUVs and trucks take on the system.
Drivers have the chance of choosing when to shift between 2WD to 4WD systems, and they can even choose the range. The better handling that the system offers is ideal when you need to traverse rough terrain.
4WD systems offer a stiffer ride compared to 2WD models. The systems are also more demanding on fuel and will increase the initial cost of the truck.
AWD vs. 4WD: Which Drivetrain Works in Ice and Snow?
Both AWD and 4WD systems are ideal for driving on slippery terrain. However, when pushed hard, either of these vehicle models can spin off the road. Both systems increase traction to the wheels to ensure the vehicle stays on the road when both the front and rear wheels are engaged.
Neither of these systems will make you make a perfect stop on ice or snow. Nevertheless, these systems are ideal when you need to drive on snow or on ice and the extra cost you incur will be advantageous.
When driving during cold days, you will encounter several conditions starting with soft snow, glare ice, all the way to hard-packed snow. In such conditions, AWD systems, which deliver power to all four wheels at the same time, come in handy. These systems will sense the conditions the vehicle drives on and send power to the wheels as needed.
AWD systems can shift power to different wheels quicker than a driver and this means no guesswork.
4WD systems are better at handling large mounds of snow. When winter gets extreme, you need a 4WD system to unstuck you from deep snow. Because all the wheels have the same amount of power, the wheels will have more traction to drive better.
Which One is Right for You? AWD or 4WD?
The system you go for between AWD and 4WD depends on the environmental conditions of where you live, your personal tastes and preferences, driving conditions, and how you plan to use your vehicle.
AWD is the more versatile of the two drivetrains. It is available in a variety of vehicle makes and models, giving you a range of vehicles to choose from. If you live in areas were winters are mild, and you only use your vehicle for light off-roading, an AWD system is better for you.
One reason why many drivers love the AWD system is that you can use as a 2WD or continuously as an AWD and the decision to switch comes from the sensors and computers. With part-time AWD systems, you enjoy better fuel economy.
If you live in areas where the weather is extreme, in remote areas, or you enjoy adventures, a 4WD system is the right for you. The system is available in trucks and SUVs, most of which have a high ground clearance. You can drive the vehicles in deep snow, on rocks, and on so many other difficult terrains.
These models offer high and low range features, so you have control over the amount of power that goes to the wheels.
How Do AWD and 4WD Systems Send Power to the Wheels?
Different automakers have different systems through which these vehicles send power to the wheels. AWD systems have an automated clutch or a differential that either sends power or cuts the flow of power to a given axle. In most cases, the clutch will operate in increments in instances where only a small amount of additional attraction is needed on the axles.
Clutches use fluid pressure. Others run on an electronic system that allows them to engage or disengage the AWD system fast and efficiently. Sensors on the system monitor several variables and send the data to the computer, which then decides where to send the power.
Automakers such as Subaru have a unique AWD system, the Viscous Coupling system. The Viscous Coupling System is one of the many Symmetrical AWD systems the automaker offers. These systems lack a computer control, and they give the driver more control on the power that goes to each wheel.
Part-time AWD systems allow the vehicle to run in two wheels. This is important when you need to save on fuel. If there is no need for additional traction, you can run the front or rear wheel and the vehicle will consume less fuel. When the vehicle needs more traction, you can then engage the other two wheels.
The shift from two-wheel to all-wheel drive occurs in milliseconds once the sensors detect slippery conditions.
4WD systems are more complicated. These do not have a clutch or differential to regulate where power goes. Instead, they have a mechanical connection with several sets of gears located inside the transfer case.
These 4WD systems mesh together several gears when engaged. When turned off, the gears are physically disconnected. There are transfer cases with unique gear sets that allow low range 4WD, which helps a truck navigate difficult terrain at very low speeds.
Low range gearing is only available in 4WD models, also designated as 4X4 models. In short, if your vehicle has a differential between its front and rear axle, then your vehicle runs on an AWD system. If the car has a transfer case instead, then you have a 4WD model.
Do Electric Cars have AWD or 4WD Systems?
Most electric cars have AWD systems, but there are still those with 4WD systems. The reason for this is that most of these vehicles are engineered for use on-road and not off the road.
Four-wheel drive systems, when used on electric vehicles, offer affordability as the motors are small and relatively affordable. Automakers can fit the motors on both the rear and front axles or can fit them on all the wheels.
Some of the electric cars with 4WD include Audi e-Tron, Jaguar i-Pace, BMW iX, Polestar 2, and Mercedes EQC.
There are several electric and hybrid vehicles running on AWD systems. Unlike in traditional gas engines, electric cars do not have transfer cases, no engine, and no complicated mechanical linkages. Instead, they have computer wires.
These systems have two, three, or four motors. The two-motor models have one motor on the front axle and the other on the rear axle. Three-motor setups have one motor upfront and two on the rear axle while four-motor models have a motor on every wheel.
Some of the electric vehicles with 4WD also offer an AWD option. These include the Audi e-Tron, Ford Mustang Mach-E, Mazda MX-30, and Polestar 2.
Closing Thoughts
Most commuter cars today feature AWD systems, even if it is available as an option. These cars have a front axle bias where they drive on the front wheels and only send power to the rear wheels on very slippery conditions.
AWD vehicles are sufficient in most driving conditions. If you drive off the road or on very rugged terrain, you need a 4 wheel drive system. Two factors that make 4WD systems better for off-road driving are the additional features such as larger wheels and the ability to shift from low range to high range gearing.