Lexus GS 450h 2008 Owner's Manual page 549

Lubrication system
Oil capacity
(drain and refill)
Oil grade
Recommended oil
viscosity
Oil viscosity:
● 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 as 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 condition.
With filter: 6.6 qt. (6.3 L, 5.5 Imp.qt.)
Without filter: 6.2 qt. (5. 9 L, 5.2 Imp.qt.)
ILSAC multigrade engine oil
Use Lexus approved "Toyota Genuine Motor Oil" or
equivalent to satisfy the grade and viscosity shown
below.
Outside temperature
6-1. Specifications
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