In aviation if I let my helicopter set in a hanger without flying it for 12 years and have all the annual service and inspections done the aircraft is considered by the FAA and NTSB to be worn out to the point it must be totally dismantled and remanufactured on the last day of the month of the 12th calendar or 2200 operational hours which ever comes first. That is maintenance. At some point every piece including the core airframe is no longer usable. There's a good reason why. I made a brief example in a previous post.
Maintenance is key, yes, but at some point continuing forward becomes stupidity. Be proud of your truck but realize there are things you guys don't understand that will get someone killed by wearing ultra high mileage on your sleeve like a badge of honor.