2006 Lexus GS 300 Owners Manual - Page 1186

CHASSIS SPECIFICATIONS (GS430) - DIFFERENTIAL Oil capacity Oil type and viscosity 1.35 L (1.42 qt., 1.19 lmp.qt.) Toyota Genuine Differential Synthetic gear oil API GL−5 SAE 75W−90 or its equivalent NOTE: The following label is affixed on the right side of the differential carrier. Use the type and viscosity shown on the label when the differential oil is replaced. NOTICE Use of differential oil other than "Toyota Genuine Differential Synthetic gear oil API GL−5 SAE 75W−90" or its equivalent may damage the differential gear of your vehicle and diminish fuel efficiency. For the reasons mentioned above, Lexus recommends use of "Toyota Genuine Differential Synthetic gear oil API GL−5 SAE 75W−90". Another differential oil of matching quality can also be used, (but note that despite the similarity in nomenclature between "Toyota Genuine Differential Synthetic gear oil API GL−5 SAE 75W−90" and oils that meet SAE 75W−90 specifications, compliance with the SAE specification does not guarantee that an oil has all characteristic required to avoid the problem described above.) If you are unable to locate an equivalent to "Toyota Genuine Differential Synthetic gear oil API GL−5 SAE 75W−90", contact your Lexus dealer for further details or another duly qualified and equipped professional. Synthetic oil information label 540