My Colorado is 2016 with 77k. I have had no issues with it. I’m new on here and I’m surprised with all the transmission issues. If I’m going 60 or so in 6th and then slow down to 50 when I give it gas it shudders. it’s almost acts like its misses for a second. It never down shifts when it does it. I bought the truck new and have never changed the fuild. From what I have read on here it sounds like changing the fluid might help or it needs a tourqe converter.