2003 Lexus GS 430 User Guide - Page 289

SPECIFICATIONS (GS430) - DIFFERENTIAL Oil capacity Oil type Oil viscosity - AUTOMATIC TRANSMISSION Fluid capacity Drain and refill Fluid type 1.8 L (1.9 qt., 1.6 lmp.qt.) Toyota Genuine ATF Type T - IV* 1.35 L (1.42 qt., 1.19 lmp.qt.) Hypoid gear oil API GL-5 Above -18_C (0_F): SAE 90 Below -18_C (0_F): SAE 80W or SAE 80W-90 *Change automatic transmission fluid only as necessary. Generally, it is necessary to change automatic transmission fluid only if your vehicle is driven under one of the Special Operating Conditions listed in your "Owner 's Manual Supplement / Scheduled Maintenance". When changing the automatic transmission fluid, use only "Toyota Genuine ATF Type T-IV" (ATF JWS3309 or NWS6500) to aid in assuring optimum transmission performance. NOTICE Using automatic transmission fluid other than "Toyota Genuine ATF Type T-IV" may cause deterioration in shift quality, locking up of your transmission accompanied by vibration, and ultimately damage the automatic transmission of your vehicle.