My previous Ford was 5k / 3months... as was the TDCi. They were stricter about the TDCi, but they relented when we told them it barely did 5k... a year.
Cite the owner's manual, then if the dealership persists, write a letter to the DTI with a cc: copy to the dealership to shut them up. All dealerships say that warranty hinges on the interval. But if they have no paper documentation in the initial agreement to back it up, they can't enforce it.
Or threaten to change dealerships. There are dealers who like to take advantage of people (note: bad apples for Honda, Toyota and Ford, too). That doesn't mean all of them do.
Ang pagbalik ng comeback...