It pays to know how to tow your late-model car

Do you know how your new car should be towed? Hauling away a late-model automobile is a lot different from towing an aging Plymouth Fury or '72 Buick.

If you're driving an economy car that was built after the mid-'70s, for instance, you should be wary when choosing a tow service. Not all tow-truck operators are familiar with the proper way to lift today's vehicles.

An improperly towed car can be severely damaged if the tow-truck operator doesn't know what he's doing.

Small cars today usually include an increasing percentage of lighter materials, such as aluminum and plastics. They also use more precise engineering (which means less rugged construction).

A few thousand miles after a tow, you may discover that the front wheels are out of alignment. Or even more drastic, some cars end up with buckled fenders, and in a few cases windows pop out of their frames. Often, some of the front-end plastic as well as the air dams get crushed beyond repair.

The American Automobile Association (AAA) is particularly concerned with problems associated with poor towing techniques. For the last 10 years, the triple-A has published its ''Vehicles Towing Manual,'' a collection of diagrams and photographs which describe the proper use of conventional sling-type tow equipment on most cars now in production.

A towing service that uses the manual, or one like it, is probably eager to do the job right. Some cars, however, cannot be safely towed by the sling, especially imports.

An alternative to the sling is a flat-bed truck, although there are some disadvantages to this method as well. If the car is fastened improperly to the truck bed, the car's frame can be subjected to abnormal loads as the truck bounces down the road. Also, ramp trucks usually need at least 35 feet of clearance to get a car onto the bed, an impossible situation in most urban areas.

Second, a tow truck with wheel-lift equipment can do the job - that is, if you can find a service station that has such equipment. Some carmakers claim this is the only way to tow a car properly. Europeans have used the wheel-lift method almost as long as they have had tow trucks.

Basically, wheel-lift equipment carries the car by either the front or rear tires so that the vehicle is supported by its own suspension. Because the weight of the car is being supported solely by the wheels, there is little danger of damaging the the plastic accessories, bumpers, or frame.

The Petersen Scoop, a wheel-lift device built in Florida, offers several advantages over conventional equipment.

Shaped like a football goal post, the easy-to-use Petersen Scoop has a two-pronged fork on the end of a pole. Once the fork ends of the scoop are positioned around the tires of the car, a steel rod is inserted behind each tire to form a cradle. As the scoop is lifted, the tires drop into place inside the cradle, with the car's weight supported by the wheels at the axle.

As added security, straps can be looped over the top of the tire and fastened to the forks to prevent the tires from rolling or bouncing out of their seating. Hydraulic cylinders, controlled from either inside or outside the cab, permit the scoop to be pivoted in almost any direction.

A further advantage of the scoop, as well as other wheel-lift devices, is that it can pull cars from tight parking spots.

The triple-A, however, has some misgivings about the system, warning that the weight distribution on the tow truck is unfavorable and can even be unsafe. Further, the lifts are initially more expensive than sling-type devices and removing cars from an accident scene can be difficult if the truck is fitted with only wheel-lift equipment.

''The road-service industry,'' asserts John Fobian of the AAA, ''is very slow to accept new ideas,'' adding that it will take at least another 10 years before wheel-lift equipment is fully accepted by the industry.