About a month ago I was driving my Yukon Denali when all of a sudden it started to tick very loud and whenever i would give it gas it felt like it was bogging out or about to run out of gas. I knew it had to be the lifter. I sent it to the shop and it was a collapsed lifter. I had all lifters replaced as well as the camshaft. I have been driving it for no more than a week when all of a sudden the same thing happens again... loud ticking and loss of power. thankfully i have a 2-year warranty. my question is. Does anyone have an idea as to why it has a collapsed lifter after i just had the whole top end rebuilt?