Just go back to post #129 - I have a 2018 Duramax L5P . . . very simple upgrade and I believe well worth the small cost. You can buy the Donaldson filters for about $26 on Amazon.Thanks for being the guinea pig, I mean volunteering your truck for this. Will be interesting to see the numbers on the UOA. Once I get my new truck I'm going to seriously look into this modification and see if it will work on the new L5p's. Hopefully someone will have already tested it out to see.