I have an on-engine CAV filter on an old Perkins diesel. There are tons of options for filters, but a lot of them look identical other than paint and markings. Does anyone know any reason to choose one brand over another? I just took off a NAPA 3166 and put on a CarQuest 86166. In the past I have used Perkins 26560017. Since there's a big Racor before this filter it probably doesn't need to do too much, and I have never noticed a problem one way or another. From reading around on the forums some people have had problems with no-name brands not fitting well. Some other options are the Fleetguard FF167 and Luberfiner L296F. I'll probably go with the NAPA ones since there is a store down the street, even though they charge a few bucks more. Only changed once a year so not a big expense.