I wouldn't use the cat filters the micron rating is no better than oem filters just a larger filter plus the cat filter was not designed for the Duramax which mounts the filter horizontal and the cat filter doesn't have an antidrain back valve so when engine is off the oil will drain back to the pan, you can check the oil level right after you shut the engine off but if it sits a while the level will appear over full when infact it may be ok or low
Cons: poor micron rating, no anti-drain valve, oil drain back, not designed for Duramax
