count me in for 2 different valve cover replacements under 30k miles. However I believe the first one was botched as upon inspection a lot of sealant was visible around the valve cover in the back and I was pushing a huge amount of oil through the turbo, eventually led to turbo failure. It was done before I bought the car though and I missed that on my inspection. Now Im pushing much less oil through my intake just the normal amount that most newer GM cars do. Both were the newer design btw. First one was done somewhere under 20k miles as It had around 20k on my car when I purchased it.