I have a 2016 Colorado base…
I have a 2016 Colorado base model 4 cyl. with the 6 speed auto transmission. Around 15000 miles I had shuttering and skipping. If I accelerated hard it wouldn't be as bad. I think the shift points are to close. In Manuel control I can shift at 3000rpm and it's fine. Dealer says can't be reprogrammed and the 6 speed transmission is a sealed component , no fluid dip stick to check levels. I have found a service bulletin that Chevy put out in 2024 for servicing these exact problems. The dealer plays dumb on these issues. Oh and by the way Chevy has a recall on the 8 speed transmissions due to a class action law suit. So if yours is an 8 speed look into it! Mine is not in the recall.......yet