I use an Amsoil Ea filter on my 2001 Jeep with a 4.0 engine as I think its the best filter one can buy with its nano fiber technology. Others have commented (on BITOG) that its a waste of money unless I plan to do extended oil changes. Right now I go 7500-8000 using PP oil. So am I wasting my money? We are talking maybe $5.00 to $8.00 more per filter which in the scheme of things (car maint. related) is not that much.