Lexus GS300 1998 Owner's Manual page 384

ENGINE
CHECKING THE ENGINE OIL
LEVEL
62G005–1
"GS400 "GS300
With the engine at operating temperature and turned off,
check the oil level on the dipstick.
1. To get a true reading, the vehicle should be on a level spot.
After turning off the engine, wait a few minutes for the oil to
drain back into the bottom of the engine.
2. Pull out the dipstick, and wipe it clean with a rag.
3. Reinsert the dipstick and push it in as far as it will go, or
the reading will not be correct.
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