Is it time to sell your car?

Dollar bill shaped like car with quarters for wheels

Life is sweet, but it would be a lot sweeter if our cars and trucks would warn us when heart-stopping repair bills or inevitable replacements lay in wait just around the corner.

Most of us, however, need help recognizing when it's time to get rid of our ride -- whether it's a 13-year-old Chrysler LeBaron convertible, a three-year-old Toyota Tacoma, or brand-new Mercedes-Benz GL-Class.

That's why we've come up with five smart moves to help you make a hard but satisfying decision.

Smart move 1. Do a lifestyle reality check.

"Our homes reflect who we are, and our cars reflect who we wish we were," so the sad (but true) saying goes. Here's where a cold look in the lifestyle mirror can go a long way. Ask yourself (or better yet, ask a friend), "Is what I drive serving my current needs?"

Your Mazda Miata may have made you the King and Queen of Cool when you were single, but when you started adding little princes and princesses to the castle, that tiny two-seat sports car became royally impractical. Suck it up, daddy, and get a midsize Mazda6.

If you live in New York City, it may be time to bid farewell to that Ford F-350 Super Duty SuperCrew. Be brutally honest. You'll be happier in the short and the long run. We know plenty of people in Manhattan who don't even own a car, and that's the perfect car for them.

Smart move 2. Do an economic reality check.

Make sure you own a vehicle you can realistically afford. Factor in every expense, not just the monthly payment. Include the price of insurance and maintenance, broken down to a monthly average, and don't forget to calculate the terror of fuel costs.

Total them up and you've found the true cost of owning your car. If you can realistically meet this number without breaking a sweat or missing a meal, month in, month out, bravo.

But if you're struggling to keep up with the bills, and spending $500 or more a month on your car or truck, you should replace it with a new ride that costs more like $250 to $350 a month to own.

When making this decision, follow a simple rule of thumb: Monthly payments shouldn't exceed 8% of your gross monthly income. If, for example, that's $3,000, then your payments should be no more than $240 a month.

Smart Move 3. Pay heed to the "Gut-Wrench-In-Its-Presence" Effect.

If merely thinking about driving your car threatens to double you over in pain, get rid of it. No joke. There is no case to be made for accepting 15,000 miles of anger a year. If you hate your vehicle -- really hate it -- and have no practical considerations that trump your decision making, then dump it, sell it, or trade it in. Life is still too short.

Smart move 4. Beware the "My Mechanic Knows My Credit Card Number by Heart" Syndrome.

If your car has been to the shop three times over the past year for repairs -- even legitimate repairs -- it's not a normal, healthy vehicle.

We live in the glory day of automobiles, where virtually every model offers breathtaking quality and reliability. The cliche is that there aren't any bad cars anymore, but the truth is there really aren't even any average cars anymore.

Planned obsolescence, the automotive industry's dastardly plan to design and build cars to last only as long as the warranty, is a myth. Bad luck, however, is not. Your vehicle may be a "Monday morning" car or an early production run of a new model (never a good bet for high quality -- new models always need time to get their teething problems out of the way).

For owners of older, very used cars, this is the rule to follow: If you must make three repairs during any 12-month period that add up to the resale value of the car, cut your losses and run.

You can find out how much your car is worth at Edmunds.com or Kelley Blue Book.

Smart Move 5. Keep an eye out for the two symptoms of big trouble.

Just remember: Blue smoke = Bad news. Blue smoke out the tailpipe means you're burning oil, which very likely indicates the oncoming need for an engine replacement. Never cheap.

Another major symptom worth paying eyes-wide-open attention to is when you notice a bit of slipping between gear changes in the automatic transmission. If you notice the engine revving without any appreciable increase in speed, that's what a slipping transmission feels like. This problem is not quite as urgent as the engine, nor quite as expensive, but transmission replacements are never a bargain.

Either one means it's time to sell.