The head was put on around 46,000. It’s been worse since then.My bad. All I had to do was scroll up to see your issues, I had forgot I had replied once already to this thread.
Anyways, your issue with the oil could be due to the oil being lost to the intercooler due to blow-by from exhaust gasses (I believe that's how it happens). Adding a catch-can to the truck could help this. I believe every 2.8 has this issue, of blow-by, but losing 1+ quart per oil change is rather excessive. So maybe it's something else...or maybe you are losing that much that is going into the intercooler and PCV. I know mine was absolutely filthy with oil residue when I added my catch can and that was just looking at the PCV: I never investigated the intercooler, I just took everyone else's word for it. You can get a good can and set up for relatively cheap (under $200). I collect 1-2 oz. of oil per oil change usually.
The other issues though, I don't know. They finally got your 4x4 issues resolved and the scored cylinder head issue could be the reason for your poor fuel economy. Have you got to drive the truck to see if things have improved since they rebuilt or replaced the engine basically, or do they still have the truck?
around 30% oil life roughly 5,000 miles my low oil light comes on... Every time. And it’s been documented every oil change for the last two years. About 3 months I change oil. That the oil was low. It’s been between 1 1/2- 1 3/4..
the dealer has torn everything apart to find where it’s going and they said no clue. So they ask gm and gm says it in tolerance. So what do you do