The short answer, "Yes."
Brad Hinton points to The Great Debate on the topic of making tacit knowledge explicit - and to the program for the July 2012 KM Australia Congress where this is scheduled to be discussed: "making tacit knowledge explicit with collaborative technologies."
Of course there are nuances to this question - just as there are nuances in tacit knowledge that aren't easily made articulate. Yes, tacit can be made explicit. But not all tacit can be made explicit. I learned this back in my graduate study days with expert systems and the various "elicitation" techniques. They work ... to a point.
On the yes side of the question, you have the simple process of asking questions. As I ask questions, you articulate answers that I might not otherwise be able to discover. This works even better if we are working in a question-answer framework that helps me ask ever-deeper questions, and helps you respond with redirecting questions of your own. (Sometimes you can help me discover that I already know the answer, I just didn't know how to think about it. But that sounds like tacit-to-tacit knowledge.) If this discussion is happening online, it may take more time, but the tacit becomes visible ... it becomes explicit.
On the no side of the question, there are always aspects that are difficult to articulate and make explicit. There is so much more behind "what you know" than what you can say or write down, that That's when I often get to the point of, "Here, let me show you," rather than trying to talk / write it out. And most online collaboration platforms aren't set up in such a way to enable deeper questioning that will elucidate deeper knowledge.