Ughhh thats unbelievable Anonymous. My second engine is knocking aswell but its not as bad as your new one. I want to bring it back and get it replaced again but at this point i dont even know if its worth the hassel. What's your next plan of action are you going to bring it back to be replaced again lol? I feel like if the service manager tries to argue about it with me about replacing it im going to see red and just go straight ape **** on him. I dont know what to do anymore man, i just feel like all of this is falling of deaf ears.