The top 10 rules of high-mileage car maintenance

Americans are keeping their vehicles longer and driving farther than ever before. Today, the average age of vehicles on the road is greater than nine years and more than 68 percent of vehicles have more than 75,000 miles.

As a vehicle's engine ages, its performance decreases and oil starts to break down at a faster rate. Over time, seals begin to deteriorate, gaskets become brittle and oil consumption increases -- all leading to a reduction in engine performance.

Treating your high-mileage vehicle with a little T-L-C and consistently following the 10 rules for high-mileage vehicle maintenance will help ensure a high-mileage vehicle will go the distance. Using premium motor oil specially formulated for higher-mileage cars -- such as Castrol GTX High Mileage Formulation -- will also help a higher-mileage car feel young again.

1. Get Regular Oil Changes

2. Find a Good Mechanic

If you don't do your own maintenance, find a shop staffed by ASE-certified mechanics (that's the National Institute for Automotive Service Excellence). A good mechanic will listen to your questions and explain procedures clearly.

3. Keep on Top of Your Tires

Have your tire pressure checked at least once a month. It's the best way to prevent unexpected flats. A service station attendant can quickly and easily perform the check. Also make sure to rotate your tires and check their alignment as part of a regular tune-up (or with every other oil change).

4. Pay Attention to Warning Signs

Of course, not every little thump or ping you hear spells disaster. Cars, like people, have their peculiarities, and you are sure to quickly learn what is normal for yours. With a high-mileage vehicle, however, it's best to check out any symptom -- be it a sound, smell or feeling -- that seems the slightest bit abnormal. Remember: an ounce of prevention is worth a pound of cure.

5. Pay Attention to Outward Signs

If your car is leaking fluids, it can mean serious trouble. Keep an eye on the conditions of your driveway or regular parking space for stains or spots that can warn you of possible leaks. Castrol's GTX High Mileage Formulation Motor Oil contains special conditioners that help protect and maintain seals, thereby helping to reduce leakage -- a common problem in older, higher-mileage engines.

6. Schedule Regular Tune-ups

Even if your high-mileage car seems fine, that's no guarantee it is. Use tune-ups to ensure your car's major components are running smoothly and that they stay that way. Your oil should be changed, tires checked and rotated if necessary, belts checked and replaced, brake lines inspected, spark plugs and air filter checked and replaced, and fuel injector checked. A good way to top off a tune-up is an overall analysis of your car's engine, and undercar, safety and computer systems.

7. Prepare Your Car for the Seasons

If you live in a sunny climate all year round, you can skip this step. For the rest of us, take a look at our Expert's Checklist of Seasonal Maintenance Practices for your high-mileage vehicle. Preparing your high-mileage car to defend against the elements will lessen its chances of needing repairs and save you money in the long run.

8. Check Your Fluids Regularly

It's dangerous for your high-mileage car to get dehydrated, so be sure to keep an eye on its vital fluids. Simply lift the hood and perform a quick visual check. Use the dipstick to check the oil level; a quick glance at the coolant reservoir will let you know if you need more cooling fluid.

9. Store It Properly

Storing your vehicle in a dry, temperate location when it is not in use will prevent disastrous wear and tear on both its interior and exterior. Garage your car whenever possible to protect its looks.

10. Stay on Top of Safety Features

Nothing is more important than your car's ability to protect both you and your passengers. Air bags, anti-lock brakes and any other additional safety features that you may have added to your car should be carefully checked by your ASE-certified mechanic on a regular basis (when your car has a tune-up) to ensure that in the event of an accident, they will perform their vital, lifesaving functions.