See also:

Kia Rio owners manual
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Rear differential (4WD)
Checking or changing rear differential fluid Have rear differential fluid checked or changed by an Authorized Kia Dealer according to the Maintenance Schedule at the beginning of this section. ...

Air cleaner
Element replacement Have the air cleaner element checked and replaced in accordance with the maintenance schedule. NOTICE Do not drive with the air cleaner removed; this will result in excessi ...