Buick 1999 Park Avenue Automobile User Manual

As shown in the chart, SAE 10W-30 is best for your
vehicle. However, you can use SAE 5W
-30 if it’s going
to be colder than 60 F (16 C) before your next oil
change. When it’s very cold, you should use SAE
-30. These numbers on an oil container show its
viscosity, or thickness. Do not use other viscosity oils,
such as SAE 20W
Use only engine oil with the American Petroleum
Institute Certified For Gasoline Engines
“Starburst” symbol. Failure to use the
recommended oil can result in engine damage not
covered by your warranty.
GM Goodwrench oil meets all the requirements for
your vehicle.
If you are in an area where the temperature falls below
-20 F (-29 C), consider using either an SAE 5W-30
synthetic oil or an SAE 0W
-30 oil. Both will provide
easier cold starting and better protection for your engine
at extremely low temperatures.