If you're using premium gas and thinking it's better for your engine, Consumer Reports says you may be wasting your money.

"Most cars are designed to run on regular gas," says Consumer Reports' Rik Paul.

Upscale luxury cars like BMW or Mercedes-Benz often call for premium.

But you might be surprised. Some other cars, like the Smart Car, Nissan Maxima, and most Acura models also require premium gas.

"But if the owner's manual says premium is recommended, you can often use regular with no problem," says Paul.

"In some situations this slightly reduces power and fuel economy, but you likely never even notice."

However, if the owner's manual says that premium is required or premium only, Consumer Reports says to stick with that grade.

Another way to save is to make your car last longer. You do that by making five important monthly checks:

  • Check the level of your engine oil. If it's low, add oil, but never overfill it.
  • Coolant. It's usually in a clear plastic container. If it's below minimum, fill it up with a 50-50 mix of water and antifreeze.
  • Check the power-steering fluid. It should be between the minimum and maximum level.
  • Brake fluid. In most vehicles the brake fluid is in a clear reservoir marked with minimum and maximum lines. If it's low, fill it and then have the system checked. It could mean there are leaks or the brake pads are wearing.
  • Checking your transmission fluid can be more complicated. Overfilling causes expensive damage, so for most people that's one check that's best left to a mechanic.

Last but definitely not least, check the windshield-washer fluid. Keep it full. It's important to keep your windshield clean, especially when there's lots of glare.

Whenever adding fluid you need the right kind. There are different types of engine oil, brake fluid and coolant. And all the answers are in your owner's manual.

With a report from CTV British Columbia's Chris Olsen