What are the minor and major service intervals for the 4.4 and are there any specific expensive elements such as timing belts at 100k or along those lines to look out for at various points.

I have noticed that low mileage one's do seem to have a premium price tag but are high milers a problem. (I'm thinking 100-120k for a 5 yr old). in my experience (I do 25-30k per yr) diesels are pretty robust and go on forever.
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