Is the Purolator oil filter still in production?
Is the Purolator oil filter still in production? The Purolator oil filter is still in production today. This original invention was a bypass filter: most of the oil flowed directly from the oil pan to the engine's working parts, and a smaller proportion of the oil was sent through the filter via a second flow path in parallel with the first. How big is a high efficiency oil filter? High efficiency (HE)[edit] High efficiency oil filters are a type of bypass filter that are claimed to allow extended oil drain intervals.[4] HE oil filters typically have pore sizes of 3...