Kia Optima Hybrid 2017 Owner's Manual page 581

Maintenance
Recommended coolant
• When adding coolant, use only deion‐
ized water or soft water for your ve‐
hicle and never mix hard water in the
coolant filled at the factory. An im‐
proper coolant mixture can result in
serious malfunction or engine dam‐
age.
• The engine in your vehicle has alumi‐
num engine parts and must be pro‐
tected by an ethylene-glycol with
phosphate based coolant to prevent
corrosion and freezing.
• DO NOT USE alcohol or methanol
coolant or mix them with the speci‐
fied coolant.
• Do not use a solution that contains
more than 60% antifreeze or less
than 35% antifreeze, which would re‐
duce the effectiveness of the solu‐
tion.
For mixture percentage, refer to the
following table.
Mixture Percentage (vol‐
Ambient
ume)
Tempera‐
ture
Antifreeze Water
-15°C (5°F) 35
9-28
Mixture Percentage (vol‐
Ambient
Tempera‐
ture
Antifreeze
-25°C
40
(-13°F)
-35°C
50
(-31°F)
-45°C
60
(-49°F)
65
ume)
Water
60
50
40
OJF075007