Are you failing to create an extract in Tableau desktop or Tableau server?
I have workaround that might work for Tableau server. Here's the trick.
Create an empty extract and publish it to Tableau server. Once extract is published in Tableau server, Refresh the extract.
Your chances of creating extract are more with Tableau server.
I thought about that too. but I wasn't able to create the empty extract due to the same reason (time out).
But I was able to optimizing the query so it is good now.
I still want to keep this question open though since this issue is still there. and btw the tableau version i was using is 10.1
Sure. Just a small note that you would not get a time out to create an empty extract. There are few tricks to create an empty extracts using parameters or extract filters.