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Posted

i thought i found my clicking noise when cold.

the upper shaft has a gear looking thing with a small amount of grease on it. it seemed to be where the noise was coming from. I added some grease to the gear. it seemed like the click, click was gone. However, this morning when the truck was cold, the click click was back. 

after about 2 lock to lock turns of the wheel, the click goes away ??‍♂️

Posted
28 minutes ago, kylant said:

i thought i found my clicking noise when cold.

the upper shaft has a gear looking thing with a small amount of grease on it. it seemed to be where the noise was coming from. I added some grease to the gear. it seemed like the click, click was gone. However, this morning when the truck was cold, the click click was back. 

after about 2 lock to lock turns of the wheel, the click goes away ??‍♂️

Greasing the splines is only half the issue..the noise is mainly coming from the plastic bearing/bushing the shaft goes through located in the firewall..try to get some grease in there as well or non petroleum based spray lubricant..it should take care of the issue for a while..not completely but for a good while.

Posted

My friend and I both have identical 2020 AT4 2500HD w/ the Duramax.  We're withing a few thousand miles of each other, me around 14k, him around 17k.

 

Both trucks are doing the steering clunk/click when going straight.  You can wobble the steering wheel back and forth a few degrees and it will consistently do it, regardless of outside temp or truck operating temp.

 

From reading this, it sounds like we're both having issues with the intermediate shaft.  Going to be making an appointment to hopefully have it fixed, and if not at least get it documented. 

 

It's a major annoyance, and it's amplified 100% when you're driving on dirt/washboard roads.

Posted
28 minutes ago, cdh7917 said:

My friend and I both have identical 2020 AT4 2500HD w/ the Duramax.  We're withing a few thousand miles of each other, me around 14k, him around 17k.

 

Both trucks are doing the steering clunk/click when going straight.  You can wobble the steering wheel back and forth a few degrees and it will consistently do it, regardless of outside temp or truck operating temp.

 

From reading this, it sounds like we're both having issues with the intermediate shaft.  Going to be making an appointment to hopefully have it fixed, and if not at least get it documented. 

 

It's a major annoyance, and it's amplified 100% when you're driving on dirt/washboard roads.

yes. same to all of that. it's noticeable and almost tolerable on normal smooth roads, but the minute you get onto uneven surfaces, it's amplified!

Posted

My upper intermediate shaft was replaced 10 days ago and so far I am happy with it.  My new truck is scheduled for production this week and hopefully I won't have this issue again.

  • 2 weeks later...
Posted
On 11/2/2020 at 4:37 PM, maynard9089 said:

My upper intermediate shaft was replaced 10 days ago and so far I am happy with it.  My new truck is scheduled for production this week and hopefully I won't have this issue again.

Don't hold your breath....I was one of the first to post on this thread and one of the first to have the intermediate shaft replaced. The problem has definitely returned and I don't think I've put 5k miles on the new shaft.

Posted
On 11/2/2020 at 11:16 AM, kylant said:

i thought i found my clicking noise when cold.

the upper shaft has a gear looking thing with a small amount of grease on it. it seemed to be where the noise was coming from. I added some grease to the gear. it seemed like the click, click was gone. However, this morning when the truck was cold, the click click was back. 

after about 2 lock to lock turns of the wheel, the click goes away ??‍♂️

this is so random. some days it does it, others not ??‍♂️

Posted (edited)

It hasn't come back to get it replaced yet, but we diag'd a truck for this and found the plastic collar/bushing that is in the firewall boot that the shaft goes through was bad.  We ordered the boot for it.  I'll try and report back when it gets replaced.  

Edited by newdude
  • 2 weeks later...
Posted

So after my intermediate shaft was replaced on my 2020 Denali there was a very noticeable improvement but I could feel every road imperfection through the wheel.  I had so many other issues with the truck that I traded it in on an identical 2021.  The new truck is what I expect to feel through the wheel.  Night and day.  So I doubt there were any changes to the parts or processes but I do plan to reach out to people at the Flint plant to verify.  What I expect is that sometime down the road this truck will experience the same issue.  Hope not but not very optimistic. 

Posted

I would be very interested in what you find out. Sounds positive the 21s don’t drive with so much road feel. My 2020 HD steering responds to every bump on the freeway. Curious if dealers give a fair trade.

Posted

I had three trucks during the early 2000s with the low speed column rattling. Usually they added grease. They always said annoying not a safety problem. My 2002 recently Avalanche purchased does it too. Kinda endearing. Wouldn’t be if I encountered it on a newly purchased truck.


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Posted
6 hours ago, KARNUT said:

I had three trucks during the early 2000s with the low speed column rattling. Usually they added grease. They always said annoying not a safety problem. My 2002 recently Avalanche purchased does it too. Kinda endearing. Wouldn’t be if I encountered it on a newly purchased truck.


Sent from my iPhone using Tapatalk

Ahhh yes! The infamous GMT800 I.S.S. (Intermediate Steering Shaft) issue.

IIRC, first recall was to repack the spline with grease. That would tighten up the tolerance for a while and the knock would eventually return.

Second recall was to replace the shaft with a revised part. When didn’t work, back to repacking with grease. 
 

The steering on my 2020 feels odd at times but overall performs well. I have the digital steering. Seems to have very, very light effort on center, possibly a quarter inch or so of play left and right off center, hard to tell. The odd part is that the truck tracks very well at all speeds. No wandering at all, tightens up nicely as speed increases. I have noticed a few instances of very slight knocking felt through the steering column. Approaching 1000 miles. 

  • Like 1
  • 2 weeks later...
Posted

Well here we are another 2000 miles since the dealer replaced the intermediate shaft and the looseness is back in the steering. the new intermediate shaft that they install seems to last about 2000 miles before some part wears enough to cause the slop in the steering. Wondering if this will justify for a buyback/ lemon program after 3 or 4 trips to the dealer or not??

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