ENGINE OIL - For instructions on maintaining proper oil level see Page 4.

The crankcase oil put in at the factory is a high quality Service M.S. oil (see below) with special break-in additives; so should be left in for the first 1,000 miles.

Ordinarily, no further break-in oils or additives are needed. However, under some adverse driving conditions if such additives are necessary, your Buick dealer has available Buick Engineer-approved products for your use.

Oil should be normally changed after the first 1,000 miles (see Page 26 for filter service) and ever 2,000 to 3,000 miles thereafter. Certain types of operation however, such as short run, low speed operation in cold weather or in metropolitan areas where driving is limited to ten to twenty miles per day, or in extremely dusty territory, calls for more frequent changing. If there is any question about the change interval best suited for your type of driving, please consult your Buick dealer.

There are several types of oil manufactured for use in internal combustion engines. For use in the Buick engine we recommend that an oil, designated "For Service DG" or "For Service MS" (formerly called heavy duty type) be used for maximum protection under all driving conditions. "For Service ML" (formerly called regular type) and "For Service MM" (formerly called premium type) are not recommended for use in Buick engines.

Engine crankcase oils have a definite effect on ease of starting, oil economy, combustion chamber deposits and engine wear. Many commercial crankcase oils contain heavy non-volatile deposits forming components which make the type of combustion chamber deposits that greatly increase detonation and particularly pre-ignition, even though these oils may be designated "For Service MS" or "For Service DG". Some commercial crankcase oils are deficient in anti-wear characteristics and may contribute to rapid wear of camshafts, valve lifter assemblies and other highly stressed engine parts. Owners are urged to use only crankcase oils that have proven to produce ease of starting, satisfactory oil economy, minimizing combustion chamber deposits and produce adequate protection against wear.

The following chart will serve as a guide for the selection of the correct SAE viscosity number oil to use under specified atmospheric temperature ranges:

If the lowest anticipated atmospheric temperature, during the interval in which the oil will remain in crankcase, is: The following SAE Viscosity Numbers are RECOMMENDED: If Multi-Viscosity Oils are used, the following grades are SUGGESTED:
Not lower than plus 32 degrees F SAE 20W or SAE 20 SAE 10W-30 or SAE 10W-20
Not lower than plus 10 degrees F SAE 20W SAE 10W-20 or SAE 10W-30
Not lower than minus 10 degrees F SAE 10W SAE 10W-20 or SAE 10W-30
Below minus 10 degrees F SAE 5W SAE 5W-20