Kia Stonic 2019 Owner's Manual page 441

Maintenance
NO. ITEM
*6 Manual transaxle fluid
*7 Fuel additives (Petrol)
8 20
Manual transaxle fluid should be changed anytime it has been submerged in water.
Kia recommends that you use unleaded petrol which has an octane rating of RON
(Research Octane Number) 95 / AKI (Anti Knock Index) 91 or higher (for Europe) or
Octane Rating of RON (Research Octane Number) 91 / AKI (Anti-Knock Index) 87 or
higher (except Europe).
For customers who do not use good quality petrols including fuel additives regularly, and
have problems starting or the engine does not run smoothly, one bottle of additives added
to the fuel tank at every 15,000km (for Europe, Australia and New Zealand)/ 10,000km
(except Europe, Australia and New Zealand, China) / 5,000 km (for China). Additives are
available from a professional workshop along with information on how to use them. Kia
recommends to visit an authorised Kia dealer/service partner. Do not mix other additives.
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