My wife has a 2014 JKU and I just purchased a 2015 JK last month. I have noticed that if the wife's JKU has sat several days without running, when the engine is first started, I get 2-3 seconds of a ticking noise from the engine right after start-up. The past weekend, I put my JK in the garage from Thursday evening until Sunday afternoon and the same thing happened. Only lasts for a couple of seconds right after start-up. JKU has 4000 miles and JK only has 370 miles as of this morning. Is this normal? It's like the engine is staved for oil for a few seconds. If the jeeps are driven everyday, I don't hear the ticking. I have noticed this a few times with my 2005 Ram truck but that's usually if I haven't driven it in a week or so. Maybe all the oil draining to the pan and it takes a few seconds to start pumping to the engine?