I have been following this thread for awhile. I work on a fleet of V-10s and they are very reliable. These trucks weigh about 16000 lbs and are standards and automatics. They are bucket trucks so most of the time they never get shut off. We get ride of them at 250000 miles on the odometer and only god knows how many idle hours are on them. We figure another 200000 miles!.We have never had a valve cover off or changed a water pump. We use only Motocraft oils. Needless to say we take very good care of these trucks. Iam a certified mechanic of 25 plus years . They did have spark plug issues on the early ones. I had to fix 4 spark plugs, easy fix. If you want some more info you can email me
rcode8v@gvtc.com .