In case anyone else is considering the new Peak fluid, my 2020 Sierra did not like it. Although, it has not caused performance issues, i began getting poor DEF quality messages intermittently. The messages will come on and then clear on it's own within a minute. I contacted Peak and they responded with the following, "Thank you for contacting us. We are aware of this happening with 2020 GM products. We have learned that General Motors has a computer software update for the exact issue you are having. This is not a DEF issue but rather a GM issue." Sent from my SM-G981U using Tapatalk