[Chipa]

Posting this from another thread to start a clean thread in case this helps other Blazer owners in northern climates

I live in MN and my 2020 Blazer started making a loud/noticeable "whine" or "singing" noise in the sub-zero temp a few weeks ago. At start of driving on a very cold day, it consistently whines or sings with variable pitch based on speed between 20-50mph. It's most noticeable when accelerating or decelerating. Once it warms up, maybe 5-8 mins, the sounds goes away. When outside temp is warmer, above say 25F, there is never a noise. It happens in both AWD and 2WD. I drove it all last winter and there were no noise issues.

Vehicle is 2020 Blazer, purchased 12/31/2019. It currently has 39K miles on it. Tranny is 9T65 M3V which I believe is same as in Traverse, Acadia and Caddy XT5/XT6.

I took it into my Chevy dealer on a very cold day and they were able to recreate noise driving it and also while on the rack.They checked for any obvious issues but found nothing. GM service bulletins didn't ID anything exactly.

Their initial diagnosis was the noise was coming from a gear in the "torque tube" so their first repair action (under warranty) was to replace the Torque Tube. This did not fix the issue, noise was same the next cold day.

I took it back in this week, and coincidentally there is a 2020 Traverse in the shop at same dealer, with about 21K miles on it with same symptoms. They had also tried Torque Tube replacement on that one - and that did not resolve. So their next action is to replace the Drive Shaft (under warranty). They are going to try this first on the other vehicle before ordering a new drive shaft for me.

I will post an update after next step.

P.S. for the repair geeks, this is not the issue discussed in GM Bulletin 20-NA-136 or 20-NA-060.

 

[Chipa]

We have 2020 with the same problem. Does it while in AWD not in 2WD. Please post when you find out of the drive shaft fixes it. Thanks!!!

Yep - Will post here when I know more. What's happening is my dealer has a Chevy Traverse customer of same vintage, with same drivetrain, experiencing exact same issue. That client is a week ahead of me - in that they also replaced torque tube first which did nothing. Now they have new drive shaft on order which has not arrived yet. They are going to do that repair to that vehicle first and if that resolve it for them, they will order new drive shaft for mine. My dealer said they have had a total of 3 customers (including me) with this issue so far. In one case, replacing the torque tube resolved, which is why GM recommended that repair first.

One key note on symptoms on mine, it happens consistently in both AWD and 2WD at cold temps.

 

[Chipa]

I’m having this issue as well. Mine does it only when’s it’s colder than -3 Celsius and usually when I’m going between 45-50 kph. It’s more pronounced in AWD than FWD, but I can recreate it in both.
So far the dealer has completely replaced the transfer case which did not fix the problem. They had another vehicle come in with the exact same problem, so it’s obviously an issue.
Anyone have any updates on theirs yet?

I checked in with my service guy just now. The new Drive Shaft they ordered for the Traverse having same problem as mine has still not arrived from Michigan yet (We are in Minnesota). My service guy told me the techs for the Traverse and my Blazer both rode in both vechicles when they were cold and the symptoms were identical. Since this is a challenging case they are taking guidance directly from GM on repair actions. I asked if there was any gloabl tracking of this general issue by GM. He said there is a "Techline" case tracking my issue but that's not something I'd be able to see or access. He re-iterated that the techs are confident the noise is coming from the back-end and the noise is traveling up to the front. (I mention this as from inside the vechicle it sounds like it's coming from front end). I'll post in main thread when I have any news. This is even more frustrating as we are now running out of winter soon to test if any fix resolves.

 

[Chipa]

Here is an update. Per GM Technline recommendation, one week ago they replaced the drive shaft in the other vehicle here in Rochester MN (Traverse) having exact same issue. Note: it took over 5 weeks for that new drive shaft to get here from GM. That Traverse owner has not been able to verify if that resolved the issue or not - because it's not been cold enough since replacement. Today I requested they order a new drive shaft for my Blazer and will get that installed in a month or so when it arrives. At this point, I won't know until next winter if that fixed the problem, but my rationale is this moves the ball forward and it "may" resolve the issue vs waiting another 9 months as the clock ticks away on my warranty.

 

[Chipa]

4/26/22 update. My replacement drive shaft finally arrived from GM this week. It's being installed Thursday under warranty. Since this issue only happens in very cold weather, I will not know until December if it resolved the issue.

 

[Chipa]

1/16/2023 - Here's an update. Above summary: Last winter they replaced (1) Torque Tube then (2) Drive Shaft under warranty. By the time driveshaft finally arrived, it was spring, so no way to determine if (2) fixed.

I now have 66K miles on my Blazer. We have not have bone-chiiling -20 F temps this winter where I've been out driving - so I wasn't able to see if this was fixed until a week ago. I was parked outside overnight in Northern WI for a below zero F night. When I started the Blazer next morning; it once again did the whine thing when moving.. however only for a very short time (~20 seconds) then all was normal.

I don't know if the two repair jobs helped any, but I decided I would not go back to the dealer unless we get another very cold snap when I can verify it's still a problem as they say there is nothing they recommend if they can't re-create the sound up on the rack.

My feeling is GM either (a) still doesn't know the root cause of this or (b) knows what the problem is and its can't be repaired or is very expensive. Either way it feels like they have their dealers throwing parts at it hoping the customer finally gives up.

I'm just worried this is not something that will result in major drive train issues when I get up over 100K miles.

 

[Chipa]

Any update on the whining noise? Did you bring your Blazer back in again? I have a 2023 Blazer RS with less than 4k miles doing the same thing. I notice it at idle and when driving. I live in ND and bought it in December, so I haven't been able to see if its just a cold weather thing or not. I have an appointment to have it checked out later this week.

I decided not to persue further at this time. Other than what I posted 1/16 I didn't hear the noise again (I also wasn't driving in really cold weather in February). My suggestion is to take it in only when they can hear the noise themselves when they put the vehicle up on the rack. I'm not sure they will do much for you if they can't recreate it. By the Way - I never heard it at idle, my noise was definitely only when moving.. it was a drive-train noise, not an engine noise.

 

[Chipa]

I brought my Blazer into the dealership today and its the transmission. I've barely had it 90 days. They are covering the cost of a rental and the transmission is still under factory warranty, but no ETA on when I'll get my Blazer back. Super frustrating.

Sorry to hear - at least they have some plan of attack to fix within warranty and are covering rental. Let us know what the fix was and if it resolves the noise. Good luck