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Posted

It’s to bad they have all these issues. It’s clearly the best looking truck out there and the 6.2 is awesome. 
the axle is floating while in 2 wheel drive and falling towards the differential and bouncing back and forth. 

Posted
40 minutes ago, Chevy sad said:

It’s to bad they have all these issues. It’s clearly the best looking truck out there and the 6.2 is awesome. 
the axle is floating while in 2 wheel drive and falling towards the differential and bouncing back and forth. 

Agreed, getting my vehicle replaced has been a nightmare and there is immediate solution for me. No dealer in Colorado wants to give up an AT4 for me to complete the replacement process, which is understandable given the market. I wish Transwest or King would help since they have the most in the state right now.

Posted
On 9/23/2020 at 3:10 PM, themightywrench said:

Just curious - I'm having my first attempt at repair tomorrow - has anyone had the fix actually work? It seems like most people got it fixed and it didn't work.

Any update on your repair?  Mine goes in this coming Tuesday.

Posted
On 9/25/2020 at 7:46 AM, themightywrench said:

Picking it up later this morning. Will update if I hear the noise anymore

No news is good news? Although I do understand that the fix could last for only a couple thousand miles 

Posted

This is totally in my opinion, I've been working on, engineering fixes, making modifications... etc on vehicles, trucks equipment for over 45 years, I'm not a back yard mechanic, I am very educated. So I think I know at least a little something about what is causing this issue.

In reference to the PIP5653G... I think GM is missing the actual cause of what is making the stub shaft hit the cross pin.

The clip and o-ring will help, short term, not permanently. The CV shaft is pushing the stub shaft inward toward the cross pin. Even with putting the o-ring in place, the new snap ring will hold the pin in place for a short time, but eventually, the snap ring will give way to the force of the CV joint, forcing the stub shaft to continue hitting the cross pin. The reason the noise stops when in 4WD is because of the force applied to the spider gears in the differential, holding the stub shaft in place. In my truck, when in Auto 4WD, if you listen carefully, the noise will come and go, depending on the road conditions, like hitting bumps, turning etc. 

 

I have a pretty good idea of a more permanent fix, but getting GM and their engineers to listen will be difficult. It only requires a slight machining of the stub shaft and the cross pin, and installing a spring loaded pin on the end of the stub shaft to exert a little pressure on the cross pin, reducing the movement of the stub shaft. I'm not saying this is the total fix, but if they never tried it, it could work, plus but it makes more sense than a 25 cent o-ring.

My idea, believe it or not, comes from a problem and fix that Ford was having in their mid "80s V6 Camshaft issue. Where the Camshaft was moving forward and hitting the Gear cover and causing excessive wear on the cover, chain and making a similar noise to what we are hearing in our trucks. It is very possibly a fix with a few modifications that could possibly work on our trucks.

 

I love my truck, and if GM wants to use my truck as the proverbial ginny pig, just give me something else to drive while this experiment is being performed. Hell, I will even help if they want me to.

  • Like 1
Posted
36 minutes ago, Ben Goodspeed said:

This is totally in my opinion, I've been working on, engineering fixes, making modifications... etc on vehicles, trucks equipment for over 45 years, I'm not a back yard mechanic, I am very educated. So I think I know at least a little something about what is causing this issue.

In reference to the PIP5653G... I think GM is missing the actual cause of what is making the stub shaft hit the cross pin.

The clip and o-ring will help, short term, not permanently. The CV shaft is pushing the stub shaft inward toward the cross pin. Even with putting the o-ring in place, the new snap ring will hold the pin in place for a short time, but eventually, the snap ring will give way to the force of the CV joint, forcing the stub shaft to continue hitting the cross pin. The reason the noise stops when in 4WD is because of the force applied to the spider gears in the differential, holding the stub shaft in place. In my truck, when in Auto 4WD, if you listen carefully, the noise will come and go, depending on the road conditions, like hitting bumps, turning etc. 

 

I have a pretty good idea of a more permanent fix, but getting GM and their engineers to listen will be difficult. It only requires a slight machining of the stub shaft and the cross pin, and installing a spring loaded pin on the end of the stub shaft to exert a little pressure on the cross pin, reducing the movement of the stub shaft. I'm not saying this is the total fix, but if they never tried it, it could work, plus but it makes more sense than a 25 cent o-ring.

My idea, believe it or not, comes from a problem and fix that Ford was having in their mid "80s V6 Camshaft issue. Where the Camshaft was moving forward and hitting the Gear cover and causing excessive wear on the cover, chain and making a similar noise to what we are hearing in our trucks. It is very possibly a fix with a few modifications that could possibly work on our trucks.

 

I love my truck, and if GM wants to use my truck as the proverbial ginny pig, just give me something else to drive while this experiment is being performed. Hell, I will even help if they want me to.

Reach out to GM in any way you can and share what you just shared 

Posted

The only question I would have is why does the other axle not have this problem? Did they make them different for each company manufacturing them? Seems the SU5 axles made by GM are fine. Would love to have an answer on this.


Sent from my iPhone using Tapatalk Pro

Posted (edited)

On the right side, there is a longer shaft that comes from the right side CV joint. The force from the CV joint is not direct like on the stub shaft. It is not directly attached like on the stub shaft. If you look at a diagram of the assembly, you will see what I am talking about. On an SU5, the stub shaft is made differently.

Edited by Ben Goodspeed
Posted
On the right side, there is a longer shaft that comes from the right side CV joint. The force from the CV joint is not direct like on the stub shaft. It is not directly attached to the stub shaft. If you look at a diagram of the assembly, you will see what I am talking about. On an SU5, the stub shaft is made differently.


Where did you find a diagram? Been curious and haven’t found one.

Thanks for the info.


Sent from my iPhone using Tapatalk Pro
Posted

Just dropped it off at the dealership this morning.  Supposed to be done today.  Probably won't be able to put enough miles on it today to see if it is fixed but will try to do so tomorrow.  The weather is also supposed to be warmer tomorrow which usually helps bring it out.

Will report back with what happens.

Posted
On 9/26/2020 at 10:04 AM, Aycock1987 said:

No news is good news? Although I do understand that the fix could last for only a couple thousand miles 

I haven't noticed the noise - however I also haven't driven that far so it's difficult to know if this is a long term fix. Seems to have worked in my initial 50ish miles of driving though

Posted

So I started a different thread not realizing that is the same problem I'm having. I took my truck(2020 1500, 5.3 w/8 speed trans, just over 9k miles) to the dealership today and showed the tech my complaint. The called me back to tell me the same everyone else is being told. GM wants them to replace my Axel Shaft along with the seals and a O-Ring. But the problem now is that the axel shaft is on back order. But they've said its fine to drive my truck and they'll call me when they get the parts in.

Posted

So got the truck back yesterday and didn't get to drive it much.  Took it for a longish drive tonight after dinner and it's back.  Made it 40ish miles.

It's not nearly as loud at lower speed, but at 40+ it's clear it's back.

Already left angry voice mail with my GM Customer Service Rep.

Only thing I am no sure is if they did the full repair in the PIP (not that I think it will work), because the O-ring is missing from the parts installed list.

Going to confirm with the dealer tomorrow to make sure they did it.

Disappointed but not surprised based on the documented history here.

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