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All Wheel Drive: Advantages and Disadvantages

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All Wheel Drive: Advantages and Disadvantages

All-wheel-drive has become a popular option on many vehicles in recent years. And why not? AWD can help you drive more safely and with more control in bad weather, even in heavy rain, snow and ice. While AWD was once found only on trucks, it has been expanded as an option on a variety of other cars.

All wheel drive advantages and disadvantages are clearly outlined when looking at these vehicles with advantages being able to drive in rain, snow, or even in mud and improving safety functions of the vehicle. Disadvantages include that AWD cars are not gas efficient, are more expensive to buy, and are more expensive to fix when the AWD needs repairing.

Those who seek AWD cars do so because they want to make sure they can safely drive in bad weather or get over rough terrain when required. This makes vehicles with AWD a favorite for those with rugged, outdoor jobs, those who have jobs that require more of them in bad weather, those who live in areas where roads and weather are unpredictable, and those who love off-road travel.

Differences in FWD and AWD

Many vehicles have part-time AWD. That means the vehicle will operate on two tires, either the front two or the back rear, most of the time. Vehicle sensors pick up when a tire starts to lose traction and the AWD kicks into gear. 

The driver doesn’t need to do anything as this is automatic. The extra power helps the slipping tire keep traction. 

AWD, once known solely as a truck feature, has always been the go-to choice for people who either work in rough terrain or who go off-roading, camping, or other places that most cars can’t go. AWD is excellent for off-road adventures or if you are driving on rough roads that can wreak havoc on your vehicle. 

You will need to understand whether the vehicle you are looking at has full-time AWD, part-time AWD, full-time 4WD, or part-time 4WD. There are shades of differences between the different types and you need to make yourself aware of each type to get exactly what you need when looking at options.

Does AWD help in the rain?

AWD absolutely helps in the rain. It helps the vehicle’s tires keep traction on the road in rain or in other bad weather. The way AWD functions is that it distributes power to all four wheels, which keeps the vehicle on the road even when the roads are slick with rain, snow, ice, or mud. 

Are AWD cars expensive to maintain?

An AWD car is more expensive to maintain than other types of FWD cars, but the cost difference depends on the make and model of the car. Breaking it down to an annual cost, it can cost around $100 extra a year to maintain on average depending on the vehicle. 

There are three areas where costs accumulate on AWD vehicles. 

Gas

Vehicles with AWD or 4WD get worse gas mileage than cars with 2WD. The AWD and 4WD vehicles need extra power to drive that power to all four wheels and that takes gas. 

Does AWD use more gas?

AWD vehicles have more complicated drivetrains than 2WD cars so they will use more gas.

Also, most AWD cars are heaving than their rival 2WD vehicles. These systems add hundreds of pounds and that extra weight means it needs more gas to run well. After all, the heart of the car, the engine, must work harder to carry all that extra weight and move at the same speed and for the same distance as a 2WD vehicle. 

The Purchase Price

It’s no secret that AWD vehicles are more expensive to buy than their 2WD counterparts. That can make a $2,000 or even $3,000 difference in price. This is one reason that car experts discourage people from getting AWD vehicles unless they face snow and ice regularly. 

More Expensive to Repair

Since the AWD is a more complex system, it will cost more to repair.

Do AWD Cars Have More Problems?

Some car experts tell drivers to avoid getting AWD unless they really need that feature, but it’s not because an AWD vehicle has more problems. They don’t. Maintenance scheduling is the same on an AWD vehicle as it is on any other vehicle. 

However, they are more expensive to fix when something goes wrong. 

AWD, how it’s constructed and put together, is a more complicated system than FWD. The general thought on vehicles is the more complicated something is, the more expensive it will be to fix. Finding more parts and the extra labor that will undoubtedly be involved will escalate the price tag. 

One of the issues to be aware of with an AWD vehicle is that the older the vehicle is, the more expensive it will be to maintain and repair the AWD system. Some of the components will fail when the vehicle gets into the high mileage zone and that is when your expenses will rise.

Related: Check This If Your Car Is Making Noise When Turning

Potential All Wheel Drive Problems

Your AWD vehicle will give you some warning signs that something is wrong. Those will appear as dummy lights on your dash and may include

  • Service Engine Soon
  • A warning message to service the rear axle
  • A warning light about the anti-lock brake system. 

When your AWD is failing, your vehicle will only operate with power going to two wheels, either front or back. Models differ on which two wheels carry the power when not in AWD, so you will need to look at your specific vehicle to get that information. 

Those that have a computerized code reader to decipher car mechanical codes will likely get a C0407 code. That usually means the differential clutch fluid is running low. To understand how this is important, you must first understand the basics of the AWD system. 

How AWD Works

There is a transfer car on the front axle shafts and the driveshaft goes from there to the back of the vehicle. The driveshaft connects to a rear differential. 

The rear differential hooks to the axle shafts and it is the axle shafts that give power to the rear wheels if you have a car that operations on the front-wheel-drive when it’s not in AWD. 

Looking at the rear differential, there are two sides to the assembly. One side contains the rear differential and the other side contains the clutch. A seal separates them. The control model is typically next to the differential assembly. It is attached to the differential clutch pump. 

The differential clutch needs fluid to work properly. The code comes on when the fluid is low. 

Reasons Why Fluid Can Decrease

Several reasons exist why fluid in the differential clutch can go down including:

  • There is a leak externally.
  • There is a leak into the rear differential.
  • The pump replacement was improperly filled or the gasket wasn’t put on correctly.
  • You have a bad clutch pump

A mechanic will look to fill the clutch oil, looking at the clutch pump, and looking at the seal between the two sides of the differential.

Does AWD wear tires faster?

AWD cars are known for the front tires wearing faster than rear tires. The reason for that is most AWD systems are automatic. The vehicle will run off the power on the front tires until extra traction is needed and power is distributed to the back tires. 

However, tires should still wear through their average lifespan of 60,000 to 70,000 miles. That’s about five years for normal driving. 

Ideally, most car experts state you should replace all four tires at the same time so they all have the same amount of traction. That is especially true if all four have worn thread. 

Even so, replacing only two at a time isn’t a safety or functionality issue. You can replace the front tires if they wear out first and replace the back ones a little later. Just make sure you have plenty of treads so your AWD runs effectively to keep plenty of traction on the road.

Related: How To Remove a Stuck Wheel On Your Car

Do you rotate tires on AWD?

AWD vehicles should have their tires rotated at every 3,000 to 5,000 miles. This is a general rule for all cars. 

While the rotation rule is the same for all vehicles, it is more important for AWD cars because tires on this type of vehicle wear at different speeds. Rotating them will help preserve the tread and keep your tires from wearing out too soon.

Conclusion

Maintenance scheduling, like oil changes and tune-ups, for AWD vehicles, is basically the same as other cars so they aren’t more expensive to maintain overall. The AWD system is slightly more expensive to keep up especially if it’s a high mileage car. They can be more expensive if something goes wrong with the AWD system.

For those who have regular snow, rain, mud, or ice, this remains a good investment. It also is a good choice for those who like to go off-road to camp or for work. 

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