Greetings, I’m new.
I have a 2006 Trailblazer EXT LT 4.2 with stock wheels and tires (for now.) Will 31” tires fit this model?

Painted the center caps they were dented so I ordered new ones. May paint the wheels this spring too.

 

You can go to a tire shop and ask if they can do a fitment test. I don't think so without a lift though.