I just took delivery of my new 2500HD LS 4/4 LLY Duramax yesterday. This is my first experience with a diesel. It has been suggested that I should carry a spare fuel filter and know how to change it. Also I have been told that new LLY takes a different fuel filter than the previous Duramax. My dealer wants $91 to change a fuel filter this sounds excessive but then I'm a newbie. When your driving the Cadillac of trucks I guess you should expect to pay. Any comments?