2004 Lexus SC 430 Owners Manual - Page 340

ENGINE If the coolant level drops within a short time after replenishing, there may be a leak in the system. Visually check the radiator, hoses, engine coolant filler cap, radiator cap and drain cock and water pump. If you can find no leak, have your Lexus dealer test the cap pressure and check for leaks in the cooling system. Lexus recommends "Toyota Super Long Life Coolant", which has been tested to ensure that it will not cause corrosion nor result in malfunction of your engine coolant system with proper usage. "Toyota Super Long Life Coolant" is formulated with long- life hybrid organic acid technology and has been specifically designed to avoid engine cooling system malfunction on Lexus vehicles. Please contact your Lexus dealer for further details. CAUTION To prevent burning yourself, do not remove the radiator cap when the engine is hot. Coolant type selection Use of improper coolants may damage your engine cooling system. Only use "Toyota Super Long Life Coolant" or similar high quality ethylene glycol based non- silicate, non- amine, non- nitrite, and non- borate coolant with long- life hybrid organic acid technology. (Coolant with long-life hybrid organic acid technology is a combination of low phosphates and organic acids.) "Toyota Super Long Life Coolant" is a mixture of 50% coolant and 50% deionized water. This coolant provides protection down to about -35_C (-31_F) NOTICE Do not use plain water alone. 320