5w40 that baby any brand synthetic (I tend to like moly m1, qsud, truck and gas all good choices) and since you don't put a lot of miles pair it will a spun microglass filter, Royal Purple, Amsoil EA, Wix XP and Fram Ultra seam to be the popular ones. Heat cycles and time ruin paper filters, if you do like one oil change a year, has to be spun microglass. The new Bronco's are gonna really be something, but nothing like those old ones. I've let 3 Bronco's go, I hate myself big time, especially the first one I bought off showroom floor and drove for 11 years. 0w40's are good options as well, they are actually built very well and act like 30 weights because they are built on the thin side most of them anyhow.
Just as important is coolant. Do you change it often? I say so because I did mess up one of my Bronco's cooling system by not changing yearly with IAT coolant. With so few miles maybe every two years, use an IAT coolant and distilled water.