There has been in the 80s and 90s sentiment for "Independence" in Kashmir but there has never been a major support for joining Pakistan. In earlier thread below opensource public opinion surveys have documented this
http://defenceforumindia.com/forum/...17-tracking-public-opinion-jammu-kashmir.html
http://defenceforumindia.com/forum/...17-tracking-public-opinion-jammu-kashmir.html