Hi all, Just logged in - registered. I bought a 2011 Yukon Denali XL. I like the truck! I have a few questions on it. Searching for "oil" is not possible (3 letter word) and oil filter didn't help. Anyway. 1) I need recommendations for what oil filter to use? AC Delco, Pure one, Mobil.... 2) Also, what would be the best oil? Synthetic? 6 quarts, correct in my 6.2 liter? 3) What motor do they call these? ( so I know what I am looking fro in other posts). I was thinking the Mobil oil filter or AC Delco oil filter. And Mobil synthetic for the oil. 4) Anything else to look for or do? 5) How many of you turned off the AFM (I think it's called). I was leaning toward letting mine run on 8 cylinders all the time. I don't think this vehicle ever towed anything. Tranny was flushed at 60,000 along with he coolant and rear diff. I believe the TPS was replaced on it, that's about it. 6) I am in Michigan, any tricks to try and slow down rust? I was planning on spraying the underneath with fluid film before winter. I sprayed inside the doors and wheel wells and tailgate to slow down rust as much as I can. It has one small spot of rust on the back quarter panel - I got a quote to fix it, but they said it wouldn't help since it is starting from the inside out. 7) There has to be a way to help it out. I've heard the GM preferred way is to unfold the weld hem and fix the rust, then bend it back and glue it or weld it or something. Any suggestions would be great. I hope to read a lot on here and gain some knowledge!! Thanks!!!