Keep your clunker

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NEW YORK (CNNMoney.com) -- Many car models did not make the gas mileage cutoff qualification for Cash for Clunkers. If yours didn't make the grade, and you are looking to save money on overall car expenses, here are some steps you can take.

1. Check your vitals

First of all, maintain things that could cause your old car to lose control and possibly cause an accident -- like your tires, your battery and your brakes. Make sure the tread isn't worn.

Remember to check your tire pressure every month on all four tires. "Get the (tire pressure) number from inside the car door," says Lauren Fix, the author of "Lauren Fix's Guide to Loving Your Car."

Check your tires when it's cooler out. If have too much air in your tires, your tires will wear in the center. If you put too little air in the tires, you'll have trouble braking and you'll lose about 2 -3 miles per gallon.

When it comes to your battery, make sure you have it checked at an auto parts store or a service station. A battery can die with no warning.

And of course, make sure you check for wear on all those little rubber bits that are on your car -- including the windshield wiper blades.

2. Maintain fluids

If you use conventional motor oil, switch to synthetic oil. Your engine runs more efficiently with synthetic oil. It costs about $5 more than conventional oil, but with synthetic oil, you can go longer between oil changes -- every 7,500 miles instead of every 5,000 miles.

Find out the last time the oil was checked says Phil Reed of Edmunds.com. If your car is really old and you don't have the owners manual that tells you when to switch the oil -- or other fluids, use your senses. Look at the quality of the fluid. "If it's dirty or smells burnt, consider replacing it," says Reed.

3. Beware the up sell

If you do take your car in for an oil change, you may be persuaded to buy a more expensive part or have a service performed that's not really necessary. An example is changing your air filter. Surely, changing the air filter will give you better fuel efficiency, but not doing so won't jeopardize the life of your car according to Edmunds.com.

Having your rotors on your tires turned is often a service that's not needed, but commonly recommended. And it's not cheap, it can run $50 a tire.

4. Know when to throw in the towel

Don't sell just because you've recently been forced into a major repair according to Edmunds. But you may want to get a sense of what other major repairs are on the horizon.

Since specific models tend to suffer identical problems, you can simply talk to other owners or talk to a trusted mechanic who works on that specific model of car. In the meantime, consider what vehicle you would like to buy and figure out the cost of monthly payments and try to squirrel away that much money every month.

-- CNN's Jen Haley contributed to this article.

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