I just dont trust most dealers around where i live, most dont know what they are doing. Theyll just end up throwing a jasper in it or putting in parts that it really doesnt need. I have some backround doing mechanical work but the 5.3s im not familiar with. I have a buddy who use to work for chevorlet and we are gonna start to tear it apart tomorrow and try to figure it out. We are both thinking its a lifter or maybe a rod. It just has this ignorant tick, not just the 5.3 tick , when i accelerate it sounds like im a ****ing spaceship lol. I ordered the service manual that has all diagnostics, but i also dont think its misfiring i didnt read a misfiring code, just a knock sensor malfunction code, and yea sadly im out of warranty by 10k miles, decided not to take the extended warranty but im sure gm would try to figure a way of making me pay some kind of money even with exenteded warranty. but fingers crossed its nothing too serious .