10 Ways You Waste Money on Your Car

To be smart about your car, you need to do the right amount of on-time maintenance — while resisting mechanics' pitches for unnecessary work. But while neglect doesn't work, neither does overspending. From Sadowski and Michael Calkins, manager of the AAA program that recommends repair shops, here are 10 ways you may be wasting money on your car.  MadOne

1. Changing oil every 3,000 miles. A relic of a bygone era, this guideline is often promoted by dealers or repair shops eager for business. Instead, read your owner's manual and follow the manufacturer's recommendation for oil-change intervals — it's often 5,000 to 7,500 miles.

2. Using premium fuel unnecessarily. Don't pay this higher cost unless your owner's manual says premium fuel is "required.

3. Failing to change your air filter. "If you have not changed your air filter by about 40,000 miles, it is probably clogged and hurting your gas mileage," says George Sadowski.

4. Failing to check the brake pads. Most mechanics will raise this issue periodically, but you should suggest it if not. Getting timely pad replacement can help you avoid later (and much more expensive) repair to the brake drums or rotors, Sadowski advises. Replacing the pads should cost less than $150.

5. Buying mileage-boosting additives and devices. 

6. Tune-ups for your engine or air conditioning. "Modern engines are constantly being tuned by on-board computers," says Calkins. "And as for air conditioning, if it is blowing cold air, it is fine. If it isn't, get it fixed."

7. Changing coolant. Mechanics or dealers will often say you need to have the engine coolant flushed out and replaced. That's only true if you have plenty of miles on it. Modern coolant — you'll know it because it's usually brown or light red — is engineered to last five years or 50,000 miles, says Calkins.

8. Ignoring your check-engine light. This amber light on your dash, which in some cars says "service engine soon," indicates a problem with the fuel or emission system. A malfunctioning oxygen sensor, often the reason for the light, can hurt your gas mileage. And an out-of-kilter fuel mix, if ignored too long, could harm the engine."You could wind up with a $1,000 repair job instead of what could have been a $150 job," cautions Calkins.

9. Buying expensive performance tires.

10. Paying for built-in navigation.