New-car sales are experiencing a slowdown in light of the economic downturn, and at the same time, record numbers of off-lease vehicles are returning to dealerships this year. As a result, many manufacturers are turning to their

certified vehicle programs to boost their used-car sales and deal with the surplus of off-lease vehicles to their dealerships.

In addition to aggressive advertising to consumers and added incentives to dealers to

encourage sign-ons, many manufacturers are leveraging to the Internet, as they realize the benefits that online marketing has for their certified programs.

AutoTrader.com, an online classifieds marketplace for new and used cars, says it has become the top choice for big-name manufacturers like Toyota, Lexus, Honda and Audi, who have been among the first to sign onto AutoTrader.com's Certified Vehicles Program. According to AutoTrader.com's research, more than 75 percent of consumers searching the site are looking for used cars, while half of these are searching specifically for certified used cars.

According to AutoTrader.com spokesperson Mira Sleilati, by partnering with AutoTrader.com, these manufacturers are:

* Exposing thousands of their certified vehicles to AutoTrader.com's more than 5 million unique monthly visitors.

* Generating traffic to their own sites from consumers that are looking for more information.

* Ensuring that their certified inventories are always up-to-date online. AutoTrader.com receives data feeds directly from the manufacturers about their available certified vehicles and matches this data with the information the company has independently obtained from the dealers, to enable consumers to search for certified-only vehicles.

* Encouraging new dealer sign-ons through AutoTrader.com, as dealers realize the exposure the Internet can have for their certified inventory.