Toyota Prius c 2014 Owner's Manual page 502

6-1. Specifications
Oil viscosity (0W-20 is explained here as an example):
• The 0W in 0W-20 indicates the characteristic of the oil which allows
cold startability. Oils with a lower value before the W allow for easier
starting of the engine in cold weather.
• The 20 in 0W-20 indicates the viscosity characteristic of the oil when
the oil is at high temperature. An oil with a higher viscosity (one with a
higher value) may be better suited if the vehicle is operated at high
speeds, or under extreme load conditions.
How to read oil container label:
The International Lubricant Specification Advisory Committee
(ILSAC) Certification Mark is added to some oil containers to help
you select the oil you should use.
Cooling system
Capacity
Gasoline engine
Power control unit
Coolant type
500
5.6 qt. (5.3 L, 4.7 Imp. qt.)
1.7 qt. (1.6 L, 1.4 Imp. qt.)
Use either of the following:
• "Toyota Super Long Life Coolant"
• A similar high-quality ethylene glycol-
based non-silicate, non-amine, non-nitrite,
and non-borate coolant with long-life
hybrid organic acid technology
Do not use plain water alone.