Engine Lubrication; Oil Numbering System - Pontiac 1953 Owners Service Manual

ENGINE
LUBRICATION
Straight mineral motor oils are satisfactory for use in Pontiac
engines under normal driving conditions. These oils are designated
by the refiners as REGULAR TYPE. Under driving conditions where
the engine is required to develop nearly full power for a large
percentage of time as in sustained high-speed driving, it may be
desirable to use mineral oils treated with additives for improving
their resistance to the effects of high temperatures. These motor oils
are designated by the refiners as PREMIUM TYPE or HEAVY DUTY
TYPE. The refiners or marketers supplying motor oils are responsible
for the quality of their products .
OIL NUMBERING SYSTEM- Practically
all oil companies have
adopted the S.A .E. Viscosity Number System which classifies lubri-
cants according to viscosity or fluidity. The oils with the lower
numbers are lighter and flow more readily than do the oils with the
higher numbers. Thus, a No. 10 oil is a light oil and a No. 40 is a
heavy oil. The S.A.E. number refers only to the viscosity of the oil
and has no reference to any other characteristic or properties. "W"
indicates an oil adapted for cold weather starting.
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