Originally Posted By: MajorCavalry
I appreciate all the replies. But, where is the support for your choice? As I asked in my original post, where do you find information about the filtering efficiency so as to make an objective decision? Or the quality of materials to be used to determine whether it will last for 5 or 10K miles?
I seem to remember an Amsoil comparison showing Toyota filter and Honda filters as being very low (50%) in filtering efficiency. Is this adequate to maintain the health of an engine? I guess Toyota and Honda think so.
I would not pay serious attention to any study or test results from Amsoil, as they would be designed to show their products as the best.
A high efficiency filter often does not last as long as a low one before it goes into bypass during cold starts, which results in a lot of additional wear. Ultimately a high efficiency filter will block sooner.
The figures quoted for efficiency need to be for the particle size that causes the most wear, not one chosen by the filter company. Also those figures are normally for a filter at the end of its life and in most cases of little interest. The figures I like to see are for a new filter, which in the case of a carboard media one will be lower than an almost blocked filter.
Major brand synthetic media filters are different, as their efficiency when new will be almost the same as when nearly full.
Quality counts a lot with oil filters, as a failure of the relief valve, media tears (Rather too common) and bad O rings can all have serious consequences. If the relief valve does not open during a cold start and the can or seal are weak, the oil pressure can rise high enough to cause a serious oil leak.
I only use OEM from a reliable source, gen Bosch, or Mobil 1.