I just bought a '16 with 12,000 miles on it and it's clunks (hear&feel) while downshifting in most gears. I stuck my edge tuner in there and tried a few different tunes but nothing helped. I noticed the converter locks up in 1st gear and stays locked during every upshift while accelerating slowly. When downshifting the converter stays locked until 2nd gear I believe. The clunking is the worst from 4-3 and 3-2. I'm pretty sure all of the clunking is because of the torque converter. I'm use to my 4l60e and 4l80e only locking up after a set speed in 3rd and 4th gears. There is no way it's normal for the converter to lockup when it does..