Smoke on start up

[Roy Mendiola]

Hey guys I’m a little worried because I just bought a preowned 2016 Silverado with 20k miles but I notice that sometimes on regular weather smokes white when starts. Not only that but the exhaust tip is all black from the inside like stained. Does anybody knows if this is normal or should I take it to the dealership? I have extended warranty up to 100k miles thanks in advance 

[Sierra Dan]

White smoke is not a good sign.

Now and then especially in cold weather, these K2 DI engines will puff a bit of black smoke on startup, but that is normal.

Get it to the dealer.