Unfortunately the Jayco "bumper to bumper" warranty does not cover water leaks after about 3 months; the owner is required to check seams on roof and sides and correct any potential leak issues, even if the potential leak area was never caulked by Jayco at the factory. Maybe you could document that you or dealer did the checks, and did not find any issues? Here is a link to a discussion on another board about Jayco and water leaks:
Jayco water leaks. Most other manufacturers have similar exclusions; I think all of them should be embarrassed about the exclusions, but they are not.