gear searching and noise from transfer case

[Jeremy Oliver]

when driving between 35-40 mph truck sounds like its searching for gears.  its brand new 2021 Sierra with 10 speed transmission. is this normal? also, just noticed today when at idle and a load in the bed hearing a growling type noise from transfer case area or near it at least.  

[Rob Mugs]

Bring it into the dealership and don't pass go.  The 10 speed 'can' be a bit different.  Adjusting from 3-4 gears (or whatever you had) to 10 but it's solid.  The t-case making noise shouldn't be an issue either.