Best Oil for the 2022+ WRX

Oil-related parts worth having

Intervals matter more than grade

This is the part of the debate that actually affects engine life, and it gets far less attention than the grade argument. Subaru's guidance is full synthetic every 6,000 miles or 6 months, with a shorter interval called for if you drive hard, take short trips, or live in extreme temperatures. **Stock and gently driven:** follow it. Modern synthetic is good and the factory interval is not aggressive. **Tuned:** halve it. Around 3,000 miles is where most tuned VB owners land, and the reasoning is straightforward - higher cylinder pressure, higher boost and higher sustained temperature all degrade oil faster. There is no cheaper insurance in a modification budget. **Short trips:** you are in severe service regardless of how gently you drive. An engine that never fully reaches operating temperature does not boil off moisture and fuel dilution, and both accumulate. **Track days:** change after the event rather than counting it against your normal interval. A single session generates more heat and shear than weeks of street driving. **Ethanol:** flex fuel setups tend toward more fuel dilution, which is another reason to shorten. Replace the filter every time. Skipping it to save ten dollars puts old contaminated oil back into fresh oil, which defeats the point of the change.

What actually matters

Rank these honestly and the grade argument shrinks. **Changing it on time** is the single biggest factor. Fresh conventional oil outperforms exhausted synthetic, and the interval is where owners actually go wrong. **Using a quality full synthetic meeting the specification** matters. Brand loyalty beyond that is largely preference. **Replacing the filter every time** matters, and it is cheap. **Checking the level between changes** matters more than people expect. Any turbocharged engine can use some oil, and running low is considerably worse than running slightly old oil. The FA24 is not known for dramatic consumption, but checking costs nothing. **The grade** matters least of the five, and only starts to matter at sustained high temperature. One thing that does not help: switching grades hoping to fix a problem. If the engine is consuming oil, running hot, or showing knock, the oil grade is not the cause and changing it delays finding what is.

The verdict

Run 0W-20 full synthetic if your car is stock and under warranty. It is the specification, it is adequate, and there is no upside to arguing with it. Run either grade if the car is tuned, and spend your attention on the interval instead. Three thousand miles rather than six is the change that actually protects the engine. Run 5W-30 if you track the car or live somewhere hot and see sustained temperatures in the 250s. That is the specific condition the heavier grade addresses. And if you genuinely want to know rather than to choose a side, monitor your oil temperature and send a sample for analysis. Two data points from your own car settle this better than any amount of reading about somebody else's.