Classic/Antique Car Repair/QUESTION MOTOR OIL


Brad, hi can you please tell me what oil car owners are using in the cars from the 20's. Would you use synthetic if the car sits in a garage. For many years I was told to use Non Detergent, for many reasons. Please let me know, thank you Ken

This is one of those questions that goes not have one set answer. If the engine is mostly original and has not been rebuilt back to close tolrances then I would use a 30W with an API rating of at least SD. The API ratings are found on a circle on the oil container any run from SA
Down the alphabet with SA being the poorest grade. If the engine is a recent rebuild to close tolerances then I would use an oil with at least SD  but a viscosity rating of 10W/30. I my self would not use synthetic oil. As far as detergent goes I would not hesitate using it as the non detergent oils are only found in the SA thru SC API rated oils and truth be told these are great oils or sewing machines and Junior's tricilce  but not in a heat developing internal combustion engine.

Classic/Antique Car Repair

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Brad Sears


All automotive including antique and collectible. However if the car has been modified I can only answer in general terms and maybe get you pointed in the right direction.


Automotive tech instructor. Syndicated auto columnist 1970's though the early 1990's. Syndicated auto radio talk show, Ask Brad About cars, CBS Radio 70's through 90's TV Show "Last Chance Garage" 1980's PBS-TV syndicated. Auto instructor for the following companies: Fram Autolyte Holly Carter AMF Ford Motor University Of Conn Blue Hills Technical School Sugar River Technical Center Grew up in a family garage in Needham Mass and turned wrenches from the age of 14.

Manchester Union Leader, Nashua Telegraph, Motor Service Magazine, Yankee Magazine, Popular Mechanics (Saturday Mechanic early 80's), Los Angeles Times, New York Times, and lots more.

More than I care to remember. Basically Franklin Technical Institute in Boston, Northeastern University, Fitchburg State Teachers College, Tufts University, and a lot of factory schools along the way.

Awards and Honors
Moto Award winner. And much more.

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