Lexus GS460 Owner's Manual page 591

The 5W portion of the oil viscosity rating indicates the characteristic of the oil
which allows cold startability. Oils with a lower value before the W allow for
easier starting of the engine in cold weather.
The 30 in 5W-30 indicates the oil viscosity when the oil is at its operating
temperature. An oil with a higher viscosity may be better suited if the vehicle
is operated at high speeds, or under extreme load conditions.
How to read oil container label:
The ILSAC (International Lubricant Standardization and Approval Com-
mittee) Certification Mark is added to some oil containers to help you
select the oil you should use.
GS_G_U (OM30C11U)
May 21, 2010 1:06 pm
6-1. Specifications
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