Cooling system > Capacity > Coolant type
Use either of the following: • “Toyota Super Long Life Coolant” • Similar high-quality ethylene glycol-based non- silicate, non-amine, non-nitrite, and non-borate coolant with long-life organic acid technology Do not use plain water alone.
Applies to: Capacity
Source: Toyota 2008 Prius Owner's Manual (OM47613U), page 467