[HWYSTR455]

"Some years ago, a study was done on oil filters that uncovered the Fram filter farce. They named AC Delco’s filter to be one of the better models. Later, AC Delco changed their design and went to a cheaper setup made by an offshore manufacturer. Even so, I definitely recommend this filter over the design of any Fram filter. In fact, I even recommend it over the low-end Wix and I (personally) prefer it over the Purolators.

The filter cartridge has a large outside diameter with deep pleats, which gives the filter element the maximum flow possible. At first glance, it appears to have little filter element media, but the surface area measure was suprising: 315 sqin. The unit had a solid top end cap because the bypass valve is at the bottom, which is a well-constructed spring-loaded steel with a nitrile seal design. The nitrile rubber diaphram-type anti-drainback valve doubles as the seal between the bypass valve and the cartridge. The only drawback to this design is that the bypass valve seats metal-to-metal against the backplate. This could allow oil from the clean side of the filter to seep back into the oil pan, but it won't allow the dirty oil in the filter to seep back. Oil that is in the main gallery usually leaks out through the main bearings anyway while the engine sits. This is a better alternative to the high-end Wix, which can allow oil to seep from the dirty side of the filter to the clean side. "

"...Here are the low-cost filters that I feel safe using, based on all this information (in alphabetical order): AC Delco, Purolator, and Wix...."

http://www.austincc.edu/wkibbe/oilfilterstudy.htm


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