Blue smoke on start-up

[kevinr1970]

My truck just rolled over 16,200 miles. I bought truck new with 32 miles.
4.8L V-8 with five-speed manual.

I left my truck sitting from Thursday night until Monday morning as I was using my 4x4 to haul some stuff around; I really don’t use my ’06 as a truck.
When I started it, a small cloud of blue smoke went drifting by the window. You might call it a puff? It was more than I get from my ’86 though. It was not continuous.
I noticed something similar a few months back after I had let the truck sit for about a week. This was around 12,000 miles.
I have changed the oil every 3,000-3500 miles except on the last change. I used synthetic and am planning on changing the oil with synthetic again at 16,500. That will be at 5,000 miles.

So my question is how concerned should I be on this blue smoke on start-up? It is not every time, just twice now after sitting for a few days.
I had read something recently about warranties not covering smoke on start-up as they considered it “normal wear”.

I know there are some GM techs in these parts and am wondering what they think. Anyone else’s opinions are appreciated too!