I had a front shock on my '11 go bad at about 20k miles. Seals blew completely and all the fluid came out all over the wheel well. Tomball Ford replaced, but it took a couple days because "parts weren't in stock". Other dealers may be able to give better turn-around or at least pre-order the shock.
Note that I have a friend in the aftermarket industry (in another state) and he says that the biggest complaint his customers have is that Ford is using really cheap shocks. some have even come apart (top and bottom tubes fully separating) on him when trying to work on vehicles. He recommends changing to an aftermarket shock when they need replacement. He even recommended this to me knowing that I wouldn't be able to have his shop do the work. If your dealer can do it quickly under warranty, that is fine. But it may be worth the cash to get a better shock and a better ride (I plan to in the next couple months).
