E'VE HEARD STATEMENTS floating around that AMSOIL SDF Oil filters are not as "pretty as some of their competitors, so they can't be as well made." AMSOIL Filters have an inner beauty that's not visible to the human eye. The Society of Automotive Engineers recognized that filter performance cannot be evaluated by visual inspection. Therefore, they created the industry standard SAE HS806 test for evaluating oil filters. The SAE HS806 test evaluates particle removal efficiency and contaminant holding capacity which are the two main functions an oil filter must perform. As you can see from the following charts, AMSOIL outperforms the competition in both areas.

The Super Duty Filter has a finer filtering media, more dirt holding capacity, heavier-duty construction and a 6-month/12,500-mile change interval recommendation which is the highest in the industry. Change a Wix (NAPA) filter two to three times as often at half the price and it will cost more. There will also be more and larger particles of dirt in your oil at all times if you don't choose the AMSOIL Super Duty.