I'm the OP. Thanks for the input. To fill in some of the blanks;
In the past, my annual mileage was considerably higher and I wore the tires out before 6+ years...or traded before the tires were this old
I plan to trade this truck in 4 years or so as I prepare to retire and enjoy life! That's part of my thoughts of getting new tires and ride 'em for those 4 years (probably at 5,000 miles/year!) rather than wait a couple of years and trade my truck with nice, new tires!
My anecdote about old tires....I was running 18 year old Maxxis tires on my utility trailer that were on my previous TT. Pulled my golf cart to the repair shop (30 miles) and about 28.5 miles of the way home....that's when she blew!! Not a pleasant experience.