6.0 PSD Amsoil System oil change interval
I bought a 2006 6.0 PSD SMB about a year ago. It has the Amsoil dual filter system and I have changed the oil and filters once so far. From the information I got from SMB and what I've read that Amsoil recommends, it says to change the oil every 15,000 miles or 1 year. It's been less than that on both counts since the oil was changed but reading many posts in this forum I'm a little nervous. It seems that many people change theirs every 7500 or even 5000 miles. I thought one of the benefits of the amsoil dual filter system is that you don't have to change it so often. What interval do most people use to change their oil for the 6.0 PSD with the Amsoil setup?
Thanks and hope I don't open a huge can of worms with this one.