You mean 5-5.5 outs. In that case you need 8.5:1, with 5 to the flop, any bet will give you at least 6:1, which is enough with implied odds. Generally, this would be an easy call, but it may depend on position. Closing the action, yes, easy call.
Also, see one of my previous hands:
http://forumserver.twoplustwo.com/showfl...=2#Post11193400 , this is also an easy action-closing call on a gutshot.