Porsche 928 S 1984 Owner's Manual page 102

E n g i n e Oils — petroleum based and/or synthetic based
Always use quality oil labeled "API Service SF
or SE" which has been approved by Porsche.
The terms SF or SE may appear on the oil con-
tainer singly or in combination with other de-
signations, for example: SE/CC, SF/CC or SF/CD.
Engine oils are graded according to their visco-
sities. The grade to be used depends on existing
or anticipated seasonal climates. Refer to the
temperature chart when selecting engine oil. If
you need to add oil, it is permissible to mix oil of
different viscosities. As the temperature ranges
for different oil grades overlap, brief outside
temperature variations are no cause for alarm.
When using SAE 10 or SAE 5 W-20 engine oil.
avoid high speed long distance driving if outside
temperature rises above the indicated limits.
Single grade oil
Porsche recommends the use of single grade oils
only if multi grade oils are not readily available.
However, engine oil changes must then be per-
formed according to seasonal temperature
changes to guard against engine damage.
Multi grade oil
For all year round driving use multi grade oil. Oil
change intervals specified in the Warranty &
Maintenance brochure accompanying the
vehicle must be adhered to, including inter-
vals for oil filter change.
Fuel-efficient-oil
For all year round driving a top quality "Fuel-ef-
ficient"-oil can have a beneficial influence on fuel
economy. Before selecting these unconventional
oils, consult your Porsche dealer.
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