Is half-ton truck big enough for a lite weight fifth wheel?

Yep, it's the manufacturers fault. They are so stupid that they have no clue about what they designed and built. Only the "experts" on RV.net who know absolutely nothing about designing and building vehicles words are bible. The manufacturers cannot be trusted, they lie in their printed info when they rate their vehicles as to how much their vehicles can tow. Every new truck owner should throw away the manual first thing and then log onto RV.net for their factual information. Check, got that.