If you have finally freed your car from the snowdrifts that piled up during the big storm, you need to take steps to prevent problems later.

Here is a checklist from the American Automobile Association's Potomac Division:

* Wash the car, making sure that you reach under the fenders and body of the car to remove road salt that could cause corrosion and rust.

Commercial drive-through carwashes generally clean the sides and tops of cars but not the underneath areas that are most likely to come into contact with salt, so it's best to use a hose to spray water up under the car to wash the most vulnerable areas. For extra protection against rust, wax the car after it has been cleaned.

* Examine windshield wipers, which can freeze during cold weather. Damage can occur when frozen wipers are turned on and scrape against the windshield.

"The constant battering of the frozen rubber can ruin them, as little pieces of the wiper come off," said Tom Crosby, an AAA representative.

Sometimes the wipers freeze to the windshield and can cause rubber damage when they are turned on, he said. Damaged wipers should be replaced immediately.

* Check for tire damage. "When you are driving through the snow, you can't see what you are driving over, and you could scrape against curbs and hidden objects in the road," Crosby said.

Motorists with questions about car care, including engine repairs as well as general maintenance, can call the AAA Consumer Auto Research Service for free advice. AAA members get priority on calls that require extensive research, but the service is available to anyone who calls AAA-CARS (222-2277) 8:30 a.m. to 4:30 p.m. weekdays, Crosby said. Written questions can be mailed to CARS, AAA Potomac, 8111 Gatehouse Rd., Falls Church, Va., 22047.

The AAA will answer questions about maintenance, mechanical problems, technical specifications, factory warranties, disputed repairs, new car products and fuel economy.

An answer will be provided within 72 hours, either verbally or in writing, according to Howard Zinn, program manager.

According to AAA Potomac, more than 89 percent of the households in Virginia, 86 percent in Maryland and 60 percent in the District have one or more cars. The average age of today's car is 6.9 years. A new car costs an average of $8,710--more than double the 1971 cost of a new car.

"At a time when cars are getting older and cost more to replace, the number of service stations that provide full-serve, under-the-hood checks has dramatically declined, making it more important than ever for motorists to maintain their automobiles in safe condition," Crosby said.

An estimated 26 million used cars are sold each year, but many buyers still make their selection with their fingers crossed, hoping they will end up with a dependable car.

To help consumers recognize the best deals, free used-car clinic is scheduled for March 9 at Sport Chevrolet in Silver Spring. All aspects of the used car market will be covered, from condition and price to financing, warranties, insurance and inspection requirements, said Mac Bickerstaff, new manager of Sport's used car department.

Scheduled speakers include George Rose, investigative counsel and chief of the automotive investigations for the Montgomery County Office of Consumer Affairs. Rose will discuss a 1971 Maryland law that provides limited warranty protection on used cars sold by dealers.

Those interested in attending the clinic should call (301) 890-6000 for reservations.