Two cousins with the same truck, one is a 2017 1500 Chevy with the 5.3 Ecotec 32k miles, the other is a 2018 with 15k. They both travel 60 miles round trip each day to work all highway miles. I have been using Supertech Dexos 0W20 with an Ac Delco filter on both at 6-7k intervals. Should I stick to the 0W20 or would it be of any benefit to start using either Mobil 1 AFE 0W30, which is Dexos approved, or Supertech 5W30 syn, which is Dexos approved also. They have both been running great on the spec'd oil.