truck27

Pipe foam inserted where I taped is my latest solution.

Front of mirror.

The mirrors and front grill are two areas I've pinpointed. I've used duct tape and weather stripping to address both.

I have this issue with tow mirror driver's side 2021 GMC 2500. Been trying to tape off areas to pinpoint but seems to be something internal catching the wind and whistling.

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.

Anyone with updates?

JMac72 let me know what they figure out please, I'd like a cleaner solution other than blue tape. Ironically when I tried using clear smooth 3m tape in place of blue paint tape, the whistle came back. From what I hear, GM moving onto the next model year and most likely no other updates will come out for 21 model.

Josh, taping off the front edge of hood over the rubber seal on the front edge of hood seems to stop it. I'm still trying to find a clean way to make that permanent. MTU alum said the problem is somewhere near that fake intake on hood. I'm thinking where I'm taping is disrupting air flow enough to reduce whistle noise. I'll try and get some pictures on here.

Update. Replacement parts were exact same parts that were on there and did not fix whistle noise. Dealer said they would contact GM again. Disappointed.

Update: Dealer ordering parts for 2020 fix as that is what tech support advised them to try. Waiting on parts currently. I did put blue painters tape over along the front edge of hood and whistling stopped, so I believe that is most likely the problem. I just hope GMs replacement weather strip replacement kit resolves it as well as the painter's tape.

Thank you MTU Alum, purchasing dealer told me they can't do anything with the 2020 bulletin, whether true or not, I am not sure. From research, I believe the 2021s have updated part number from that bulletin addressing the 2020s. It's definitely noticeable above 55. It is dependant on wind direction I believe. I may tape areas around hood to test. I had a 2010 Ram 1500 that whistled from the grill area, the next year they added a weather strip to hood. Unfortunately stuff like this annoys me especially when they have wind tunnels and engineers who I would think spend countless hours on testing interior cabin noises. I reached out to another dealer waiting to hear back if they find anything. Please let me know if you find anything, thank you.

I just bought a new 2021 GMC 2500 and high pitch whistle heard from front as well over 50 mph. There is a service bulletin for 2020,Bulletin #20-NA-035, but nothing on 2021. Any insight from anyone? My guess is similar issue a the 20s but you would think they would have fixed for the 21s if a bulletin is out. https://gm-techlink.com/?p=12784

Has anyone else received letters from consumer legal services regarding this issue? It stated that several trucks have had issues and noted the Michigan lemon laws. I figured it was junk mail, but I decided to search the vibration issues and harsh shifting issues that the letter addressed. I came across this thread. I have a 2014 ltz 5.3 4x4 double cab. Truck was basically everything I want in a truck. Currently 6000 miles. No major vibrations yet, but I have noticed the occasional hard shift/clunk similar to when the rear dif started to fail on my 1997 ford explorer awd. Only other current complaints of mine include the high frequency noise I hear when depressing and releasing accelerator in awd; I have seen other forums on this issue. They claim quietest cab, but their own electronics are very audible in my opinion; if you have sensitive hearing as I do. Does not do in 2wd. Second, gm needs to take a look at what ram does for their mirriors when it comes to dimming. My 2010 ram had full dimming mirrors for all three mirrors. Not just an insert in driver's mirror and non dimming on passenger side like this current truck. Third, better resolution back up camera. My 2015 mustang much better resolution. I realize minor issues but just felt like adding to the list. I will keep posted on vibration issues. Great truck for the price as long as i don't encounter these drive line issues. Only 36 mo. lease, so at least I will only be SOL for a few years if major issues arise. Thanks for reading.