I leased a 2023 At4 1500 built in mexico in june of 2023. I noticed the chirp since day 1 and it is all of the above mentioned. Under low loads, low rpms, and startups. Im noticing it more frequently and it sounds like its under the cab rather than under the hood. I have just under 3k and thinking its time to do something about it. I dont have a reliable or trustworthy dealer near me. I drove an hr away to pick this truck up and traded in my 2023 canyon at4 i owned for 1 month. That is another problematic truck story. Thanks for the info. I feel a little better knowing its not just me having this issue. Some of the answers have me feeling a little worse lol uggg. Ive leased 3 other sierras and they're progressively getting worse and more expensive. My 2018 sierra all-terrain x was $50k msrp