I've only owned the truck since last Feb(and it was colder then, than now) and never noticed this before:

Was only around 40F when I went to start. I know the cold advance sound and feel, so I'm not too worried about that, since it didn't last very long. But I had shakes (kinda like a miss stumble) for about the first 10-15 seconds, then it went away for about 20 seconds, then came back for only a few more seconds, then went away again for good. Only noticed a little more blue smoke than normal.

Everything seemed fine after that for the rest of the day.

I'm wondering if it got advanced a little too far? But why would the shake come back for a bit after it went away? When it came back the cold advance sound seemed to not be as bad, so that makes me think it's NOT timing related. GP's are Bosch and are only 2 years old at most, but will check them by ohm's tomorrow.

Again, why the shakes?

Thanks