Originally Posted by Andrew R Stewart

Besides the noise is there a functional issue? If not, then I suggest just flushing and lubing the freewheel. The creaking is likely from rough bearing surfaces (be they rust or pitting) and/or a lack of lube. Freewheels really like a slight freeplay, call it negative preload. As long as it's not enough to cause auto shifting the freeplay, onto itself, is not usually an issue. However a slightly tight/too great a preload, can cause all kinds of coasting problems. Andy