One of the most successful new enterprises in the small town where I live (population about 2,000) is a garage which specializes in keeping old motorcars looking and running like new. They do an excellent ''rehab'' job.
I am told that there are larger communities where dozens of such shops exist; taking a car of almost any vintage and rebuilding both body and running gear. Sometimes this is ''classic'' car stuff at prices out of the range of ordinary mortals. But a lot of it is just keeping the cars used by plain, ordinary people lasting longer.
There was a time, not so long ago, when those Americans who bought new cars would turn them in every three years for a newer car. Partly that was because the standard American car more or less kept its appearance and its running capacity for three years, after which major repairs would be normal.
Back in those days the American motorcar industry took it for granted that it would sell somewhere around 11 to 12 million new cars a year.
During last year, 1981, the number of new cars sold in the United States was down to 7 million, and better than a third of those were foreign imports. This year sales are running even lower. The probability seems to be that the American market will absorb only some 6 million, or perhaps even fewer, in 1982.
Auto management and unions are working together in plans for a mighty assault on Congress this fall for legislation to curb foreign imports on the theory that somehow all will turn well for Detroit if only those ''wicked'' foreign cars can be kept off the American market.
But isn't this overlooking some solid facts about changes in American habits?
First of all, cars don't any more need to be turned in every three years to avoid major repair bills. Thanks to imports, particularly from Japan and Germany , and to governmental pressures, the American public can get cars which last well over three years. Bodies don't rust out as they once did, particularly on the salted winter streets of snowbelt states. People wanted, demanded, and got rust-defiant cars.
Thanks also to the foreign imports Americans no longer feel that they have to turn in their cars for different-looking new models. In our family we have a 1978 car which in all respects looks like the latest model of the same thing. Its paint is unfaded. Its performance is perfect. We can't think of any reason to turn it in - not even to ''keep up with the Joneses.''
There are other smaller factors. Driving habits change. Americans used to ''go for a drive'' just for something to do. But that was before the days of television - and jogging. How often in your family do you say, ''Let's go for a drive'' - just to look around the town? Once it was a large part of the average American family's life.
The plain fact is that the market has shrunk. It is highly unlikely that the American automotive industry will see another 12 million new cars a year for a long time to come, if ever.
We are not yet at the end of the ''automobile age,'' but we are certainly on the downhill slope of it, just as we have been on the downhill side of the ''railroad age'' from the time President Dwight D. Eisenhower launched our modern system of superhigh-ways. Those highways took most passengers and much of the most lucrative freight traffic away from the railroads.
What is to be done about it?
Cutting down on the imports would not make Americans want to buy more cars. Part of the market is lost. And thanks to the imports the manufacturers in Detroit are well into production now on better and much more modern cars, produced more efficiently.
Even if Congress did decide to ban all imports, there would still be a million fewer jobs in the American motorcar industry. Modernization of plants with automation is cutting the work force.
Just as has already happened in textiles, railroads, and farming, modern methods and changing technologies and life habits mean a drastic permanent reduction in employment in steel and automotive industries. Legislation can no more bring back employment as it once was in the automotive industry than it can revive the ghost towns of the old ''Wild West'' or put passengers back on the rail-roads of America.
Nor, incidentally, can these reductions in labor in old industries be fairly blamed on Reaganomics. America is in transition. Mr. Reagan did not cause the changed conditions which have already cut the number of jobs in the automotive industry by a third, and probably in the end by a half.
Mr. Reagan has had much to say about trimming the methods for tempering the pain of readjustment for those whose jobs have disappeared, but not for the loss of those particular jobs. Nothing Mr. Reagan, or his political critics, can or would do is going to revive the old levels of employment in the old and dwindling industries.
The Milburn Wagon Works was once a major employer in my home town, Toledo, Ohio. Would it have made sense for the government to try to keep it going by subsidies and tariffs?