My 2008 was at the dealer for a routine oil change and my wife was told I need a new water pump. The underside of the hood was dotted pink. We were told it was leaking from a valve. Car gave no symptoms of a problem at that point. Had the work done this week. Car has 31,000 miles, yet it was covered by warranty?? I paid nothing out of pocket. Is there a "hidden" warranty on water pumps b/c of known problems? Why was this a warranty item? Appreciate your thoughts. Thanks.