Hi Jacob, my 2019 tahoe squeaks in the cold weather. If you push up and down on bumper or even entering/exiting truck, hitting bumps, it squeaks. We figured out it is brake line which is rubbing on metal bracket. ( bracket is right below back passenger door). If you jiggle the black brake line correctly, you can cause the squeak (especially when cold out).
They just released a bulletin in November for a fix. It requires special tape to be wrapped around the line where it passes through bracket. Fingers crossed that it will correct the problem.. i am waiting on my upcoming appointment for a fix.
Hope this helps!
