New member, thanks for the add.
Our 2019 with the 5.3 V8. After sitting a couple days and somewhat cold weather here on the first startup for the day I get a second or so of engine rattle. Not a piston slap or main bearing rattle but a trashy sounding clattering. Hard to describe. Now at 12,000 miles and I'm going for a third oil change. Would a better oil help this than the usual Dexos? I see a Dexos 2 oil out now. I also see a Dexos 1 version 2 that I guess is for little turbo motors, pretty sure that's not what I'd want for the V8 here. This would be a dealer service (until the warranty runs out) so I'm stuck with what they have. Any opinions or suggestions appreciated. Thanks.