2021 GMC 2500 Issues

[truck27]

2021 GMC2500 SLE current issues:

1) Whistling noise from front edge of hood over 50+ mph. Very annoying. I had the tech link for 2020 and still whistles (20-NA-035). If I put painter's tape along entire front edge of hood and over the weather seal strip I can stop it, but obviously I don't want tape on there and can't open the hood without removing tape. Has anyone had this issue and found a solution. Only option is leaving at dealer for them to try things but I have a feeling they won't get anywhere.

2) Whistling noise from driver's side tow mirror that goes away when I fold them in.

3) Squeaking from rear leaf springs, there is a tech bulletin (21-NA-138). Just have to get into dealer for them to confirm and order parts. Anyone had success with this tech bulletin?

 

Otherwise I like the truck. Thank you in advance for any help.