My 2 year old suddenly refuses to swallow hard food!?

He will drink anything, and eat things soft like pudding, but any hard food he will suck on and then spit out. Doctor examined him and said there is no health problem. There has been no traumatic event that me or my husband recall that would have scared him to this point. Has anyone else dealt with this? I really don't want to take him to some kind of specialist, as our insurance is terrible.