Q. One painter, who uses a standard oil-based brand and adds a pint of transmission oil to each gallon, claims that the paint will last for 15 years. I am skeptical. What do you say? Rodger Wolf Queens Village, N.Y.
A. From what I can find out, you'd better stay that way -- skeptical, that is. We checked out your question with a veteran West Coast paint consultant and here is what he has to say:
''I thought I'd heard of every concoction that painters could come up with as far as blending their own mix is concerned, but I must admit the man that adds a can of transmission oil has forced me to open my mind and keep listening because that's a new one on me.''
''I would suggest he let his friend, the painter, paint his own house with this concoction, but not your reader's house.
''As far as not having enough oil in paint, the most successful house paints now have no oil in them. The best product, in our estimation, is a pure acrylic house paint. You clean up your brush, roller, etc., with water when you are finished.
''This judgment is not something we've grabbed out of the air. There is solid proof in both laboratory and field tests which leaves absolutely no doubt that oil-based paints, as we have known them over the years, are about passe.''
Get in touch with a reputable paint dealer in your area. Ask him to inspect the house and advise you how to go about the job, how much paint it will take, what kind to use, etc. Then buy the paint from him and go on with the job.
''Above all,'' says our consultant, ''stay away from the backyard chemist and his can of transmission oil.'' If you have a home-building or upkeep problem, ask a veteran West Coast builder for a solution. Send questions to: Real Estate Editor, The Christian Science Monitor, One Norway Street, Boston, MA 02115.m