howdy all, 2020 sierra SLT here.
My personal concern is, not so much the tail opening when the hitch is on, it's the tailgate open while the trailer is hooked up. The tailgate is definitely getting messed up hitting the trailer built in jack. i called GMC and they said, that shouldn't be a problem and no on else has complained. i'm like, it should be a fairly simple software code because the truck knows when the trailers hooked up, so have it disconnect the tailgate. they said, if they get enough complaints the might look into it.