2010 Chevrolet Colorado Transmission problems

My transmission in my 2010 Chevy Colorado would shift out I took it to the dealership and they hooked it up to the computer and they said my transmission was pretty much shot. I ordered a new one had it installed and the new one is having the exact same problem as the old one. Wont shift out try to operate the transfer case tryed shifting it from 2hi to 4hi you can hear the transfer case engage and the front axle engage but still wont shift thru the gears. Tryed shifting from 2hi to 4lo while it was in neutral doesnt engage and the light flashes for about 5 seconds and returns back to 2hi. Talked to an ASE certified mechanic and he said it sounds like the tccm or the selector switch on the dash. Would the transfer case cause the tranny to not cycle thru the gears?