Some on BITOG may have already read this, but for some that have not.
http://www.gmtruckcentral.com/articles/oilfilterstudy.html
It looks like the Amsoil, Fram Ultra, Mobil 1, and Royal Purple oil filters did the best.
http://www.gmtruckcentral.com/articles/oilfilterstudy.html
It looks like the Amsoil, Fram Ultra, Mobil 1, and Royal Purple oil filters did the best.