kcfx4,
I have enjoyed your questions and see that you are looking for affirmation for how you choose to maintain your stuff. I'm 54, have maintained a fleet of vehicles, ag. equip., and OPE equipment for 30 years, and I still wrestle with maintenance intervals and practices. Most of my equipment accumulates less than average miles/hours per year.
IMO, vehicle/equipment maintenance schedules vary so much between mfg. that it indicates that even they are not in agreement about what's best.
I use the manual as a bible under warranty, as a guideline after that. I adjust my maintenance schedules to fit my conditions.
Caravan - lifetime tranny fluid/filter? No way.
JD Tractor Hydraulic/Tranny Fluid - every 1200 hours, no time designation? I cut that in half (about 5 years) due to H20 condensation.
JD Air filters - change annually/no hours spec.? No way, thats only 150 hours for me.
In some cases I extend the intervals and others I shorten. There is no correct answer for everyone. As I accumulate experience with each piece of equip., I sometimes modify the intervals.....this, from a "cookbook/by the book" kind of guy.
I do tend to err on the conservative side, though. It's hard to justify pinching $10 or $20 dollars on a $25,000 dollar machine. I also don't change my tranny fluid every OCI like some here. Moderation......is the key to happiness in MY case.
Also, if no else likes or agrees with what I do, phooey on them....kind of.....I enjoy the respect I get for having a reputation of taking good care of my stuff.