HOUSTON --If you have a high-efficiency washing machine -- or maybe you're thinking about buying one -- there are some things you should know: We found some of those machines require a little more maintenance. They are one of the most expensive appliances most of us eventually have to buy so whether you have a brand new high-efficiency machine or an older model, front loaders require a lot more maintenance. And if you don't protect your investment, it could cost you. With so many options, so many features and some really slick machines, shopper Michelle has a really tough decision to make. "There is a lot to compare," she said. After researching several washing machines on the internet, she is sold on a high-efficiency top loader after she learned front loaders may require more maintenance. "It's one more thing to deal with," she said. To learn more about how to properly take care of high-efficiency washing machines, we turned to the experts at Village Plumbing and Luis Castro. He says with any high-efficiency machine, you must use laundry detergent that has the "H E" (high-efficiency) logo on it. He says a lot of the service calls he goes to is because people are using the wrong detergent. "What will happen is the machine is not going to work properly as far as the washing. This machine will not take as much water as your regular machine," Castro said. This creates a bigger buildup of soap residue. And with any high-efficiency, front-loading machine, it does require some maintenance in cleaning the rubber gasket. "Stuff tends to stick on this gasket as opposed to a top-loading washing machine," Castro said. If you don't clean the gasket every six to eight weeks, you could get a buildup of gunk and a moldy smell can leach onto your laundry. We decided to see how much buildup there was in a machine that had not been maintained for months. After just a few wipes, you can easily see the slimy gunk build up that had been caught in the rubber gasket. "That buildup there has just a really bad smell," Castro said. Castro recommends you use a product called Affresh. It's a washer cleaner and it removes and prevents odor-causing residue that can occur in all brands of HE washers, so you should clean your machine every month. A package of three tablets is $6.99. Other things you can do to maintain your machine is to wipe down the gasket after each use, leave the door ajar when you're done doing laundry for the day, and use very little, if any, fabric softener. If you don't maintain your front loader, your gasket will eventually have to be replaced because the mold will be too hard to remove. The cost to replace a gasket, depending on your model, could cost you $300. We called several appliance repair businesses for their opinion and they tell us the front loaders definitely require more maintenance and are more expensive to repair. But most technicians say front loaders typically clean better and are more energy efficient.