OP here - I finally got my truck back this week and the noise that made me ask about a problem is still there
. Honestly, the noise isn't bad and I really don't even mind but it's just kind of funny. I mainly just asked since I was in for an oil change. I have the lifetime warranty so I suppose I'll just wait for something to fall off the truck
I was a bit skeptical that they actually did anything but definitely smelled some new parts burning in for the first few times I ran the truck.
What I'm hearing is just kind of a loose rattling at startup. Seems to be coming more from the back of the truck. Dealer says they couldn't find anything else but the manifolds. Oh well, I got new manifolds for $100. Can't beat that.