Lexus GS430 User Manual page 557

NOTICE
D Be careful not to spill engine oil on the vehicle
components.
D Avoid overfilling, or the engine could be damaged.
D Check the oil level on the dipstick once again after
adding the oil.
Engine oil selection
"Toyota Genuine Motor Oil" is used in your Lexus vehicle. Use
Lexus approved "Toyota Genuine Motor Oil" or equivalent to
satisfy the following grade and viscosity.
Oil grade: ILSAC multigrade engine oil.
Recommended viscosity: 5W−30
62L042
Outside temperature
SAE 5W−30 is the best choice for good fuel economy, and
good starting in cold weather.
If SAE 5W−30 is not available, SAE10W−30 may be used.
However, it should be replaced with 5W−30 at the next oil
change.
ENGINE
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