Does your AWD vehicle require special maintenance?

by Tony Molla, ASE Master Technician

Nothing makes visiting relatives and friends easier than an SUV, especially if it has all-wheel drive. They offer lots of space for passengers, store plenty of cargo and can handle just about any road condition.

How do you know if your all-wheel drive vehicle is ready for holiday travel? Are there special considerations if your vehicle has all-wheel drive.

Anytime you travel for the holidays—especially when traveling far from home—check all the major systems of your all-wheel drive vehicle. You don’t want to be left out in the rain, literally.

Generally, an all-wheel drive vehicle has the same maintenance requirements as a typical two-wheel drive family sedan. There are a few important exceptions, however.

Mechanically, all-wheel drive vehicles distribute power to all four wheels. Two-wheel drive vehicles generally utilize power on one or both of the wheels in front or back.

The extra traction of an all-wheel drive vehicle means it provides more driving stability.

For example, when driving on a wet road in a front or rear-wheel drive vehicle, if the wheel with power loses grip, the vehicle becomes unstable and can be difficult to steer.

In contrast, one wheel of an all-wheel drive may slip but the other three wheels maintain power on the road. That’s why snow inspection stations often allow all-wheel drive vehicles to travel without tire chains. It also is the reason all-wheel drive vehicles are safer on wet roads.

SUVs typically become a family workhorse—driving teens to and from soccer practice, hauling trailers of firewood, packing hundreds of pounds of camping gear on the rooftop. The extra duty affects your vehicle’s engine, brakes, battery and tires.

As an example, hauling hundreds of pounds of gear and a carload of teens increases wear on tires. The extra weight also increases brake wear.

These and other advantages make driving an all-wheel drive vehicle a joy, but may also require some extra attention. Before heading out for the holidays, be sure to inspect the following:

• Get the brakes inspected on all four wheels, especially if your vehicle’s brakes have not been replaced in 30,000 miles (48,000 km). Your all-wheel drive vehicle typically uses disc brakes on every wheel, and they tend to wear out at the same time. The precise wear pattern depends greatly on your personal driving habits.
• Check tire inflation and wear. Your all-wheel drive vehicle needs good gripping ability since power is distributed on each tire. Heavy loads cause extra wear. Low inflation causes sidewall damage.
• Inspect battery terminals for corrosion. If your all-wheel drive vehicle is the family shuttle bus, chances are mobile accessories are putting a strain on the battery. Talk to your service advisor and have the battery tested if you see fuzz or any other corrosion on the terminals.
• Get an inspection of the all-wheel-drive system, which distributes power to front and rear axles. Every all-wheel drive vehicle has unique maintenance requirements for transfer case fluid and replacement.
• Keep up on other “pre-flight checks.” That includes regular oil changes, windshield washer and other fluid checks, tire rotation, headlight aiming/inspection and annual windshield wiper bladereplacement.

Remember, these simple maintenance checks before holiday travel can help prevent you and your family from getting stranded hours away from home.

Tony Molla is the vice president of communications at the National Institute for Automotive Service Excellence and an ASE Master Technician.