Motor vehicle filter structure having visual indicator of useful life

Filter media and filter structure or media pack can be engineered to exhibit high initial efficiency and to surface load particulate removed from a gaseous stream. The filter technology protects engine operation from ingested particulate and accumulates the particulate as a surface loaded layer visible on the surface of the structure. The particulate accumulates as a surface loaded layer until it achieves a certain depth of particulate or gray scale characteristic or color depth indicative of the end of the useful life of the filter prompting a change of the filter structure. The filter structure is characterized by its ability to surface load particulate, avoid accumulation of particulate in the depth media and enhance the characteristics of the material through surface loading. Such technology is particularly useful in light duty vehicle maintenance technology.