Difference Between AWD and 4WD
All cars in the word fall under one or two of these categories. Cars of different shapes and sizes are made to perform differently on different surfaces. Most drivers know the drive system their car has but few understand how they work and differ from one another.
How To Know If A Car Is 4WD, AWD, FWD, RWD, or 2WD
Front Wheel Drive
This is the drive system found in majority of vehicles. As their name suggests, front wheel drive vehicles drive all their power to the front wheels.
Front drives are often implemented because of their ability to make the car compact and free space in the cabin. To tell if a car is front wheel drive, there are a few things to check.
Check the engine location. Cars with the engine in the front can indicate either front or rear wheel drive. The position of the belt should guide owners on whether or not a car is a front wheel drive. Engines mounted from back to front with facing backwards indicate the car is FWD.
Check the manual: All car specifications are found in the car manual. In addition, the type of vehicle can guide owners on what drive system their car uses. Family cars and minivans tend to be FWD.
Rear Wheel Drive
RWDs drive their power into the car’s rear wheels. It is the oldest drive system in vehicles dating back to the 70s. Rear wheel drive can handle a lot of horsepower and more vehicle weight. This makes the car more stable as there is even distribution of weight.
And since the majority of the weight is positioned over the front wheels, the car has good traction. This is the reason it is often found in sports cars and performance cars, big cars and race cars.
To know if a car is rear wheel drive, there are a few things to check:
Engine position:
If a car’s engine is at the back, this means the car is a rear wheel drive. This is not to mean that cars with engine at the front cannot be RWD. If the engine is at the front and is placed from front to back making the belts face forward, this indicates a RWD.
Type of car:
Full size SUVs and tracks are mostly rear wheel drive. Check the manual.
Search the vehicle online:
Manufacturer’s websites contain details about their cars. An online search will show if the car is RWD or not.
What are the benefits of RWD?
Different types of cars have different wheel drives. For instance, muscle cars, police cars and emergency vehicles are mostly rear wheel drive. Also, most cars made before 1990 are RWD.
Full size SUVs and tracks are rear wheel driven too. If the car in question is not in any of these categories, check the engine orientation. If the engine belts face forward toward the front of the car, the car is likely to be RWD.
This method of checking is however not the best since different cars have different engine designs. Cars with engines at the back also indicate RWD. If all these ways don’t help you identify the drive design, a quick Google search of the car’s description will reveal what you need to know.
Advantages of Rear Wheel Drive
Drifting:
For many sport car enthusiast, drifting is a key part in sporty driving. As much as this wears out the tires, it’s a fun filled activity to engage in. It can also be used to take a corner quickly and turn the car around in a very small space. This technique requires high skills and is not recommended for amateur drivers.
Even weight distribution:
It is much easier to get a 50/50 weight distribution in a RWD than any other wheel drive. This has significant impact on the car’s handling making it more effective in high speed.
Better handling in dry conditions:
Since power is exerted to the rear wheels, the down force increases due to load transfer during acceleration. This makes the rear tires able to take acceleration and curving than the front tires.
Cheap to maintain:
The mechanics of a rear wheel drive are simpler compared to other wheel drives. It does not involve packing as many parts into a small space as a FWD this requiring less specialized tools to fix or repair parts.
Disadvantages of Rear Wheel Drive
Heavy weight. The drive shaft in RWD that connects the engine at the front to the axle at the back adds a considerable amount of weight to the car. An RWD will slightly weigh more than a FWD but less than a 4WD.
Difficult to handle on low grip surfaces or slippery surfaces since there is no traction control in RWD.
The presence of transmission tunnel reduces interior space of RWD vehicles.
Four Wheel Drive 4WD VS 2WD
Also known as 4×4, 4WD vehicles function in RWD mode until four wheel traction is needed. 4WDs tend to feature two sped transfer case with high and low ranges.
Unlike other drive systems, 4WD is driver activated through a secondary shift gear or a dedicated button. Four Wheel Drive is mainly found in SUVs, trucks and pickups because it offers off road traction.
To identify a four wheel drive, one has to look at the following:
- Check for a secondary 4WD gear or button
- If the vehicle is a truck or SUV, there are high chances it’s a four wheel drive
- Check the car manual
- Search for the car online
4wd vs 2wd. The difference will not really come to light unless you are living in an area where you have offroad tracks, very steep slippy inclines or a poor winter full of snow. 4wd then comes into its own.
With a 2wd vehicle in winter snow and ice can be a problem. You can obviously make this much easier to negotiate by fitting proper winter tires.
4wd is required when you are living in an area that has constant snow in the winter months, or you are regularily offroad sorting out things along dirt tracks or steeper inclines. 2wd will struggle in any of these situations.
All-Wheel Drive
All-Wheel Drive are often mistaken with 4WD because of their ability to employ all four wheels. However, this is not the case.
AWD operates by sending power to the front wheels and rear wheels on every launch prevents decrease in traction hence allowing the driver to have control over all wheels simultaneously. This gives the car more power on rough terrain such as snow and gravel.
The following are differences between AWD and 4WD:
A major difference between AWD and 4WD is that AWD is found in multi axle (more than four wheels or axles) vehicles like cargo trucks and military vehicles. In 4WD cars, just four wheels are powered.
Another difference is that AWD provides permanent all axle control while 4WD provides two axle control up until the driver switches to 4WD mode. This technically means that an AWD cannot be driven in 2WD mode while a four wheel drive ca start as a 2WD then switch to 4WD when needed.
The amount of power provided to the axles in AWD is different whereas in 4WD, all axles/wheels are given equal power. So when taking a sudden turn on mud or snow and AWD will allow the outer wheels to get more power. This provides the driver with better control and better traction on tough terrain.
There a number of ways to tell if a car is AWD.
Look underneath the vehicle when it’s off. If you see the axle shaft running from the front to the rear axles, the car is an AWD.
Check the manual. If nothing is mentioned about AWD, the vehicle probably does not have the feature. Do an online search.
Handy Kit For Your Auto
Two Wheel Drive
2WDs are the standard in vehicles. They work simply by the engine powering two wheels while the other two are allowed to spin freely.
Since the engine only uses energy to move two wheels, it doesn’t have to carry the weight of a 4WD or AWD and this makes vehicles with 2WD lighter. They are setup to be FWD or RWD depending on which two wheels are being powered.
To know whether a car is 2WD, check whether it’s a FWD or RWD. However, most family cars, sedans, and minivans are 2WD.
RWD Driving Techniques
Rear wheel drive is the most preferred drive system among petrol heads. This is because of their balanced performance and in turn better handling.
RWDs spread out most of their car weight evenly from the front to rear and this is why most race cars are rear wheel drives. However, for inexperienced drivers it might prove dangerous to handle especially in adverse weather conditions such as rain and snow.
RWD in rain
Anyone with a RWD will tell you that they are at their worst when it’s raining. Even with modern traction control systems, RWDs are prone to traction loss on slick roads.
This is majorly caused by the weight of the car being evenly distributed rather than more weight being exerted on the axle.
It’s common knowledge that the more weight you have on the axle, the more traction you have on those wheels as there is more force pushing down on the wheels to create more contact with the road.
For an inexperienced driver, this might be dangerous as controlling such a car requires experience. The same problem applies to RWDs in snow. Since snow is slick and slippery, an RWD car would slide more compared to a front wheel drive.
This has been the main disadvantage of rear wheel drive cars for a long time but can be fixed by getting a rear wheel drive with 4×4 mode.
Driving Techniques on a RWD car
Now that we know the workings of a rear wheel drive system, there are a few driving techniques to be employed when driving to ensure safety and good maintenance habits.
There are many common mistakes inexperienced drivers make. Avoiding them goes a long way in ensuring the longevity of the car and the safety of the driver. They include:
Don’t mash the throttle while making a turn:
This is a mistake done by people who are coming off front wheel drive cars. In FWD cars, if you give it too much throttle you’ll understeer – fix this by lifting off the throttle and you should pull back onto line without a hitch.
If you then mash the gas pedal the amount of grip available will be lower than normal, and you’re going to lose traction on an RWD, which ultimately causes the vehicle to lose control.
Don’t brake or lift sharply off the throttle:
If you oversteer the car, lifting sharply off the throttle might be the most natural reaction. This is wrong as it will lift the weight off the rear wheels and provide even less grip than you had before. Instead, ease off the throttle to minimize the effects of weight transfer.
Don’t pull the handbrake without depressing the clutch:
This applies to all cars but hurts rear wheel drive cars more. This is because a lot of strain will be put on the transmission and engine.
Since the handbrake’s job is to slow the rear wheels, not depressing the clutch will cause the transmission and engine to be under heavy load trying to fight the handbrake to turn the wheels.
Don’t go out in the snow or rain without suitable tires:
Rear-wheel drive cars typically have less weight above the driven wheels, meaning you’ll just end up digging yourself deeper without going anywhere near where you actually want to be going.
Avoid wrongly timed downshifts:
If you downshift too early, the rear wheels will lock up, which has the same effect as yanking the handbrake. As much as this affects any car, it is more disastrous in a rear wheel drive car.
Tips for driving Front Wheel Drive in snow
Driving is snow can be a tough thing especially without the right car or wheels or both. There are however a few tips you can apply when driving in snow to make the experience much better.
Front wheel drive means that the front wheels receive torque (power) from the engine. The power is sent to the front wheels of the vehicle to provide traction and make it move. Since the weight of both the transmission and engine are on the front wheels, FWD delivers improved traction.
The following are some unique features of front wheel drive vehicles:
Better Fuel Economy:
Since they are generally lighter than rear wheel drives and all wheel drives as they do not require the same differential components, they consume less fuel. The vehicle isn’t carrying any around extra weight making it fuel economical.
Decreased Acceleration:
FWD have lower acceleration due to all the weight being on the front tires. When accelerating, the weight of the vehicle transfers to the rear wheels and as a result less traction is provided on the wheels receiving power. This in turn reduces acceleration of the car.
Braking:
Unlike other wheel drives, if you brake suddenly in a FWD vehicle the weight is transferred to the front wheels causing the rear of the car to become lighter. If the driver makes a sudden turn while at it, the car will spin aggressively.
Things to avoid in front wheel drive vehicle
People, especially the ones moving from rear wheel drive, make mistakes when they get into a front wheel drive vehicle. Here are some common mistakes they make:
Failure to adjust driving style:
This is problem common to people transitioning from RWD. They tend to carry over old driving skills into a FWD which just doesn’t work. It results in slow lap times. In FWD, you can’t use power to adjust the attitude of the car mid corner.
Giving it more power would actually be a mistake and would cause you to under steer. The best way to deal with this to deep brake, turn slightly earlier than usual, and then straighten the wheel fast on the exit.
This reduces stress on the front tires allowing car to accelerate from the corner neatly.
Left foot braking:
Before you dismiss this as a track-only technique, it’s not. Learning how to manipulate the brake with your left foot is a skill that will help make you a smoother, quicker, and more importantly, safer driver on the public road.
Not being able to over steer:
To get a FWD car to slide, you can use one of the following techniques. One is to use traditional lift-off over steer. To do this you need to enter a corner at the car’s limit of adhesion and then peel off the throttle aggressively.
This will pitch the vehicle’s weight forward, causing the car to transition into a slide. To catch it, turn in and get on the gas.
Complain that FWD is wrong-wheel drive:
FWD are often superior to RWD. For instance, take a bumpy rough road, a FWD would be much easier to drive than a RWD.
FWD is also confidence inspiring. For drivers who are looking for their first performance car, you can’t go wrong with a nice FWD hatchback. They’re easy to learn, you can practice a variety of driving techniques, and they tend to be good value for money.
Tips for driving in snow and ice
What makes it difficult to drive in snow is loss of friction between the wheels and ice. Traction control systems in cars today can control wheel spin.
The issue with these systems is that they’re reactive which means they only start working when you’re already in trouble. It’s much better to avoid the problems to start with, and this is where the technique comes in.
Pull away and accelerate gently. In slippery conditions, FWDs tend to lose steering control when you accelerate aggressively. Accelerate gently to be able to control the car.
Quickly recover from wheel spin.
Avoid sudden driver inputs. Driver inputs include braking, accelerating and gear changes. As you already have limited grip, don’t try overload the tires unnecessarily.
Make use of ABS systems. Anti-lock braking systems are in majority of cars today. If you do have ABS, you’ll be able to tell when it comes on by feeling a pulsation on the brake pedal. If this has occurred do not force down the brakes, rather keep a firm pressure on the pedal for maximum effectiveness.
Control speed down slopes. Descending down a slope requires slow speed so you can be able to control the car in case it slides. Be careful while going down icy slopes. Engine braking is important as it resists wheel lock.
Conclusion
All these drive systems have their own benefits and downsides. There is no ‘bad’ drive system as it depends on the needs of the driver, the situation, location and day to day driving habits.
When buying a new vehicle, research on factors such as performance and fuel consumption of these drive systems to make the best choice.
FAQs
Which performs better in snow – FWD or AWD?
This is a no brainer. AWD will always perform better in snow that a FWD car. What really makes a difference though is the tires. A FWD car with snow tires fitted will perform well in snowy conditions. It will have plenty of grip as the winter tires are far superior than summer tires.
A AWD car fitted with summer tires will still perform ok, but nowhere near as good as with snow tires fitted. You are still likely to have issues with a AWD car with summer tires fitted in snowy conditions.
It is an Insurance requirement in many countries to have Winter Tires fitted in certain months of the year. Check with your insurance company on this as if you are involved in an accident and you have summer tires fitted in winter you are likely to get a much smaller payout.
In lay man terms in the FWD the power is concentrated on the front wheels while in AWD it is on all four wheels.
The AWD will perform better as the tires tend to be depressed in snow and if you are using a FWD you will need more power to pull off the stuck wheels. However, for heavy snow areas ensure your car is supported by either transfer case or limited slip differential.
Is there a difference between 4WD and AWD?
4WD has mostly been used for large SUVs that come with an extra gear shift to engage all wheels power. While in both cases both cars use all their wheels, the term AWD is mostly used for cars that drive on all their wheels irrespective of them been saloon or SUVs.
