Lifter noise?
 

My 08 Legacy/Outback has been making noise in the cold weather. I think it might be lifter noise, but I'm not sure. The car has 111K on it, runs great and uses no oil. It does have piston slap, during cold temps, but this seems like an additional noise. It has the SOHC 2.5 and I think these engines have solid lifters. What I don't know is, how often do get need adjusted and how difficult is it? Both the piston slap and the lifter noise go away completely after it reaches operating temperature. I could kick myself for not looking at this when I replaced the head gaskets last spring. It would have been much easier at that time.