The other I day Pulled the dipstick with the engine running and noticed I had blow by looking smoke coming out on the dipstick tube. I can take the oil fill cap off and turn it upside down and it stays on for the most part minus the engine vibration. The blow by coming out the oil filler tube puffs.. Last September the dealer did the head gaskets... any input is greatly appreciated thanks! The truck is a 2015 lml with 53,000 miles on it.