1938 Cadillac V16 - GM Heritage Center

the owner must estimate the lowest atmospheric temperature
that he expects to encounter throughout the winter period.
He must then select an anti-freeze solution sufficiently concentrated
to prevent freezing at this lowest anticipated
temperature.
When the engine crankcase is being refilled, the engine oil
should be selected, not on the basis of the atmospheric temperature
existing at the time of the change, but on the anticipated
minimum temperature for the entire period during
which the oil is to be used. Unless the selection is made on
this basis, difficulty in starting will be experienced at each
sudden drop in temperature.
The viscosity grades of engine oil for use in your LaSalle
car at the various cold weather temperatures are given in the
following chart:
If you anticipate that the minimum
atmospheric temperature Use the grade
will be:
indicated:
Not lower than 32°F. above 20-W or SAE-20
zero.
As low as 10°F. above zero. 20-W
As low as 10°F. below zero. 10-W
Below 10°F. below zero. 10-W plus 10% kerosene
NOTE: 10-W oil plus 10% kerosene is recommended only
for those territories where the temperature falls below 10°F.
below zero for long periods.
During summer weather the use of 20-W or SAE 20
engine oil will permit better all-around performance of the
engine than will the heavy body oils. SAE 30 oil may be
used if it is expected that the average prevailing daylight
temperature will be 90°F. or above, or if the car is regularly
driven at high speeds.
SAE Viscosity Numbers
The viscosity of a lubricant is simply a measure of its body
or fluidity. The SAE viscosity numbers mentioned in this
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section constitute a classification of lubricants in terms of
fluidity, but without reference to any other properties. The
oils with the lower numbers are lighter and flow more readily
than do the oils with the higher numbers.
The refiners or marketers supplying the oil are responsible
for the quality of the product. Their reputation is the car
owner's best assurance of quality.
The SAE viscosity numbers have been adopted by practically
all oil companies and no difficulty should be experienced
in obtaining the correct grades of lubricant.
Maintaining Oil Level
Check the oil level every time gasoline is purchased
and add oil as necessary. The float type oil gauge is
marked "F" (full), "Y 2
", and "E" (empty). Add oil whenever
the level is below "F," but add only enough to bring
the level up to "F." Always be sure to have the right amount
before starting on a long drive.
Changing Crankcase Oil
Oils have been improved greatly, driving conditions have
changed, and improvements in engines have lengthened
considerably the
life of good lu*
bricating oils.
It is, however,
necessary to
change the
crankcase oil
whenever it becomes
contaminated
with harmful
foreign materials,
to assure
continuation of
best performance
low maintenance
cost and long
engine life.
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