I have been using the FS-2500 since 1996 and I tell you this filter works great. When I got the FS-2500, the guys at Filtration Solutions said that I would be able to double my oil drain interval and go 20,000 miles per drain. Well, for over 4 years I have been going 40,000 miles per oil drain and my oil samples are perfect and my engines runs like new. When I first bought the FS-2500, I installed it on a new 379 Peterbilt with a 550 CAT 3406E engine. I drove that truck 478,000 miles. In that time I changed my Shell Rotella T 15/40 oil every 40,000 miles, which saved me over 36 oil drains and nearly $4,000.00! The FS-2500 saved me over 10 times what it cost me. You can not beat that with a stick! Now, I have a 2000 379 Peterbilt with a 550 CAT engine, I still use the FS-2500, I still use Shell Rotella T 15/40 and I still change my oil every 40,000 miles. When I got my new truck my Peterbilt dealer reinstalled my FS-2500 on it before I took delivery. This is the same filter that already paid for itself ten times over on my old truck and is working hard for me on my new truck. If you are a trucker, you should give the FS-2500 a try. No other filter that I have ever heard of does what this one does. There is nothing out there like it!