it has 95k on it. so thats why i wouldnt think to be the chain. how would you go about the crank learn re-sync? and no noise from engine at all. i have a lot of engine experience work at jd dealer for 10+ years and work on all of my own cars and trucks. is the wifes car and she took to dealer and they said 3k to fix and should just trade it. so to me its probably something simple instead of cam chain since it is spring tensioned instead of old style gm products.