Kia Optima: Tire ReplacementIf the tire is worn evenly, a tread wear indicator will appear as a solid band 1/2 inch wide (12.7 mm) across the the tread. This shows there is less than 1/16 inch (1.6 mm) of tread left on the tire. Replace the tire when this happens.
Do not wait for the band to appear across the entire tread before replacing the tire.

Tire Rotation
Compact Spare Tire ReplacementFuel Filler Cap. Description and Operation
Description
A ratchet tightening device on the threaded fuel filler cap
reduces the chances of incorrect installation, which seals the fuel filler.
After the gasket on the fuel filler cap and t ...
Installation
•
Install the component with the specified
torques.
•
Note that internal d ...
Repair procedures
Operation and Leakage Check
Check all of the following items:
Component
Procedure
Brake Booster (A)
Check brake operation by applying the brakes durin ...