AFE Power

aFe Power builds intake, exhaust and filtration for performance and diesel applications — over 200 parts across cold air intakes, filters and exhaust systems.

Their intakes are sold in distinct filter media and it changes what you should buy. Pro 5R oiled cotton flows the most and needs periodic cleaning and re-oiling. Pro DRY S is a dry synthetic that flows nearly as well with no oil at all — worth choosing on a vehicle with a mass airflow sensor, since over-oiling a filter is the classic way to contaminate one.

Diesel is a large part of the catalogue, where intercoolers, charge pipes and exhaust manifolds address heat and flow limits rather than filtration. On a tuned diesel these become the actual restriction long before the air filter does.