Hopefully that is the end of your problems.
Not sure about the '04 but I had an '05 Coachmen Cross Country that I recently sold, besides the spin on filter that is easily accessible it had a second(primary) filter that was in-line, this filter was about 1 1/4" in diameter and approx. 6" long it was mounted on the passenger frame rail above the rear axle, most of the Freightliner dealers didn't even know that it existed until they pulled it up on there computer had to be a contortionist to get under there and change it.
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