Old-time gasoline service stations are fast fading from view. They are being replaced by filling stations. You just fill your tank and go.

The gas-and-go station offers no service. There's a much higher profit on oil than on gas, yet the attendants don't even want to check your oil.

Perhaps this makes economic sense, but I doubt it.

When the OPEC carterl tripled wholesale prices, motorists began patronizing "discount" stations, and the gas-and-go boom was on. But now that the full service station is becoming scarce, one can wonder whether it is time to pause for reflection.

For example, readers have recently been asking me why so few stations provide free air these days. Either the machinery is out of order or it has disappeared entirely from some stations.

I put the question to Vic Rasheed, executive director of the Greater Washington/Maryland Service Station Association. Vic represents station operators in their battles with the major oil companies.

"The problem," he says, "is the attitude of the oil companies. They want the motorist to just buy gas and forget about service - what they call gas-and-go, and what some people call gas-and-go-to-hell."

Vic says that although some station operators now pay as much as $2,000 a month to rent their stations from the majors, the companies will no longer perform even "simple maintenance functions." The free-air tower, he says, is "just one of the casualties."

He charges that as the equipment deteriorates, "many companies just scrap it instead of rapairing it." He says some operators dig down into their own pockets to provide free-air service because they still think a serive station ought to provide service.

But the result is not always what they hope for. Too many people drive in to put air in their tires - and then drive to a gas-and-go to buy their gasoline at a lower price.

If you know how to resolve this problem to everybody's satisfaction, there are thousands of gasoline retailers and millions of motorists who would like to hear from you. Meantime everybody involved is unhappy, even the major oil companies, which have been crying all the way to the bank.