You just have to recognise that the V-10 is a higher-revving engine that the old big-block Fords and Chevys. I was brought up on engines that most Americans wouldn't think were good enough for starter motors. My first car, a 1938 Austin 7, had a 750cc L-head engine that could generate maybe 20 horsepower on a good day.
After a couple of years as an engineer in the motorcycle industry, I got used to engines that ran in the 12,000 to 18,000 rpm range. I even saw a Honda 50cc engine at the Isle of Man TT that had a peak torque at 16,000 rpm and peak power at 24,000. With such a narrow power band, it had an 18-speed transmission. I figured the rider had the cluth pulle for maybe 25% of the lap.
The "higher" revving V-10 in my F-53 doesn't give me any heartburn. It's a lot less than 24,000! I figure Ford has got the longevity covered. In any case, I only do about 4000 miles a year, so even if it's as big a POS as the old 429, it'll still outlive me!
I regularly go through the Cascade mountains in Washington State and I've never had a problem. Last season we came over Washingtom Pass on SR20, westbound, and on the whole climb to 5200 feet from Winthrop, running 35-40 mph, the coolant temp never budged off "Normal". As far as I'm concerned, the V-10 is like a Whirlpool washer - it just does whtever you demand from it and doesn't give you any dreck.
Frank and Eileen
No longer RVers or FR owners