I just started noticing about 3 weeks ago that mine is noisy too. I have 68,700 miles on mine. But its not that normal hydraulic lifter tap its actually a chater like sound for about 5 minutes and when I start to drive as the RPM's go down it will chatter. Does it for about 10 minutes total and as the temp gets to average it quits and wont start tapping until the engine cools down. It's going to my "5 star" dealer this morning. I hope its not an arm and a leg...