Best Air Filter for Prius 2008
 

Not sure how much of an effect an air filter is going to have on MPG. Of course a new one is going to do better than an old dirty one, but what about so called performance models?

Anyone have a favorite brand or just go OEM.

A filter is designed to flow the amount of air needed at maximum power output. We never really cruise and very rarely accelerate at maximum power output. Therefore, air filter flow really isn't important for fuel economy.

I just buy whatever paper aftermarket filter.

I knock the dirt off mine every couple years and put it back in.

A dirty air filter only restricts air into the engine at wide open throttle. At all other times, the throttle is restricting airflow.

OEM is fine...but so are just about ALL of the aftermarket units. So, buy the cheapest and merely change as prudent/necessary.

See the bottom of this page for a study showing that a dirty air filter doesn't hurt mileage with a fuel injected vehicle. Gas Mileage Tips - Keeping Your Vehicle in Shape