Light Duty Oil Filter FAQs

Q. What does the printing on the dome of your filter mean?
A. This is a production date code. It is a manufacturer's unique way of identifying the day, the year and, in some cases, the production facility where a particular filter was manufactured.

Q. Does your filter contain a "check" valve?
A. Depending on the vehicle application, a filter may contain a by-pass valve, an anti-drain back valve, neither or both. Whether the filter contains any type of valve or not is the engine manufacturer's design decision. Contact us for detailed product specifications.

Q. What is the by-pass valve in your filter set at?
A. Bypass valves monitor differential pressure-between the oil pressure coming into the filter and the oil pressure leaving the filter. Oil filters with integral by-pass valves are set for oil pressure differentials as specified by the engine manufacturer, and tested at all operating temperatures. Contact us for detailed product specifications.

 Q. What is the thread size of the filter?

A. Thread size varies from filter part number to filter part number.  Contact us for detailed product specifications.