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22,500 miles (36,000 km) or 18 months
❑ Inspect air cleaner filter ❑ Inspect vacuum hose ❑ Replace engine oil and filter (22,500 miles (36,000 km) or 36 months) ...

SIX-SPEED AUTOMATIC AND MANUAL TRANSMISSIONS
Hyundai's commitment to making the Hyundai Sonata extremely fuel efficient continues with a six-speed automatic transmission with SHIFTRONIC manual control or a standard six-speed manual transaxle ...

Change to "winter weight" oil if necessary
In some climates it is recommended that a lower viscosity "winter weight" oil be used during cold weather. See section 8 for recommendations. If you aren't sure what weight oil you s ...