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Posted
1 hour ago, AJMBLAZER said:

Pretty sure people have reported the noise with SU5 front axles. 

So far I've only heard of issues with the the SU4 axle which is made by American Axle Manufacturing. The SU5 axle is listed as GM Manufactured but I believe they sub that out to Delphi-Nexteer. What I'm not sure of is if the SU5 axle is only on the Trail Boss model which may be a longer axle like what GM provides with their 2" suspension lift or if certain powertrain packages require the SU5 axle.

 

Now that it is getting colder out the noise seems to have lessened. It's a real challenge to understand what would be different between the axle types as well as the influence of ambient temperature to cause the noise. So for now I wait while BBB processes my claim and call the dealership once a month to find out if the regional brand quality manager has gotten any updates from GM Engineering. Unfortunately there doesn't seem to be any other options as GM is definitely not in any hurry to fix it... 3 model years of vehicles and counting.

  • 2 weeks later...
Posted

Happy to say this will be my last post. I ran auto four-wheel drive for about eight weeks after researching and finding that it wouldn't hurt my drive train.  I initially thought about running it that way permanently and from time to time I would switch back to two-wheel drive. I'm happy to report that I no longer have the jingle and I've been running two wheel drive for several months. I don't know if auto four-wheel drive was the reason or it just needed about 15,000 more miles, but this is my story.

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Posted
10 hours ago, Philo Beddo said:

Happy to say this will be my last post. I ran auto four-wheel drive for about eight weeks after researching and finding that it wouldn't hurt my drive train.  I initially thought about running it that way permanently and from time to time I would switch back to two-wheel drive. I'm happy to report that I no longer have the jingle and I've been running two wheel drive for several months. I don't know if auto four-wheel drive was the reason or it just needed about 15,000 more miles, but this is my story.

Good to hear Philo!

I cannot say that mine has corrected itself as the noise seemed to lessen or even go away with the winter temps.  When it gets warm though (mid 40s and higher) the noise comes back.

 

At this point I'm going to do the GM Suspension Lift Kit as it replaces the front CV axles.  If the issue goes away completely then I know 100% it was the SU4 axle.

 

Posted
On 12/2/2021 at 9:31 PM, Chris Panke said:

So far I've only heard of issues with the the SU4 axle which is made by American Axle Manufacturing. The SU5 axle is listed as GM Manufactured but I believe they sub that out to Delphi-Nexteer. What I'm not sure of is if the SU5 axle is only on the Trail Boss model which may be a longer axle like what GM provides with their 2" suspension lift or if certain powertrain packages require the SU5 axle.

 

Now that it is getting colder out the noise seems to have lessened. It's a real challenge to understand what would be different between the axle types as well as the influence of ambient temperature to cause the noise. So for now I wait while BBB processes my claim and call the dealership once a month to find out if the regional brand quality manager has gotten any updates from GM Engineering. Unfortunately there doesn't seem to be any other options as GM is definitely not in any hurry to fix it... 3 model years of vehicles and counting.

 One axle is made in Mexico and the other in the States.  There is no selection process for what vehicles they go in.   The Trail Boss axles are irrelevant to the differential they go into.

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Posted
On 12/16/2021 at 10:52 AM, Gangly said:

 One axle is made in Mexico and the other in the States.  There is no selection process for what vehicles they go in.   The Trail Boss axles are irrelevant to the differential they go into.

Share your information sources.  Per GM regional brand quality the SU4 axle is made by American Axle and the SU5 is made by GM (most likely subbed out to the former Delphi plant now run by Nexteer). Country of origin isn't known and to be quite honest doesn't matter as same manufacturing processes are used around the world.

 

Haven't seen anyone share yet which axles go on the Trail Boss or if a Trail Boss has the same issue. It is relevant because the factory lift on the Trail Boss is same as GM factory lift that is sold as aftermarket accessory for non Trail Boss models. It comes with a different diameter cv axle to compensate for the increased angle at the differential.

 

I had the dealer install the lift with the new cv axles and so far the noise is gone. GM Engineering won't authorize repairs of replacing SU4 axles nor differentials as that doesn't fix the issue. But it seems a different axle part number (oe- different axle design) may fix the issue. So in that perspective it is relevant to know if the Trail Boss axle is yet a different part number with corresponding RPO code.

Posted
1 hour ago, AJMBLAZER said:

The noise doesn’t come from the CV shafts. It comes from the axle stub shafts inside the front axle. 

Right, the axle shaft as a component of the inner CV joint of the front axle assembly. 

 

All I know is that on my truck the noise comes from the driver's side axle assembly. With truck on the ground the passenger side inner CV joint is tight (almost no movement). However, the driver side inner CV joint has movement and makes definite metal on metal sound. Again the passenger side doesn't have this at all.  After the GM suspension lift with new front axle assemblies was installed the driver side is now tight without metal on metal contact noise.  So, seemingly corrected so far.

 

If I had to guess, I would say there is a tolerance stack up on certain axle assemblies married to certain front differentials that causes a poor fit. So the inner cv joint is "loose" and floats around in 2WD but is engaged in AWD so the noise goes away.

 

Does that sound plausible?

Posted

Maybe. However the GM fix and attempts weren’t about the cv shafts but the stub axles inside the diff. They replaced my driver’s side stub shaft and it fixed it. Still using original CV’s. 

Posted
1 hour ago, AJMBLAZER said:

Maybe. However the GM fix and attempts weren’t about the cv shafts but the stub axles inside the diff. They replaced my driver’s side stub shaft and it fixed it. Still using original CV’s. 

When you say stub shaft do you mean the outer ring axle (or roller housing) at the inner cv joint? The "short" or "stub" axle mating to the front differential in the attached image.

 

If so then that makes sense because that is the component that fit loosely on my truck. My dealer won't attempt a repair though because of the GM bulletin. 

CV-axle.jpg

Posted

On my 2019 silverado high country 6.2 i put a 2 in leveling kit in the front and the noise is gone. 

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Posted
15 minutes ago, Chris Panke said:

When you say stub shaft do you mean the outer ring axle (or roller housing) at the inner cv joint? The "short" or "stub" axle mating to the front differential in the attached image.

 

If so then that makes sense because that is the component that fit loosely on my truck. My dealer won't attempt a repair though because of the GM bulletin. 

CV-axle.jpg

Neither. That assembly is the CV shaft/axle. You buy it as one unit. The stub shaft is the short axle shaft that goes from the differential to the end of the axle where the Cv shaft attaches. 
 

https://www.rockauto.com/en/catalog/chevrolet,2020,silverado+1500,5.3l+v8,3444633,drivetrain,axle+shaft,10439

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Posted
9 hours ago, Jma0421 said:

On my 2019 silverado high country 6.2 i put a 2 in leveling kit in the front and the noise is gone. 


I’m glad to hear there’s a fix. Thanks for sharing. I’m looking at a few options with UCAs.

Posted
On 12/18/2021 at 7:46 AM, Chris Panke said:

1) Share your information sources.  Per GM regional brand quality the SU4 axle is made by American Axle and the SU5 is made by GM (most likely subbed out to the former Delphi plant now run by Nexteer). 2. Country of origin isn't known and to be quite honest doesn't matter as same manufacturing processes are used around the world.

 

3) Haven't seen anyone share yet which axles go on the Trail Boss or if a Trail Boss has the same issue. It is relevant because the factory lift on the Trail Boss is same as GM factory lift that is sold as aftermarket accessory for non Trail Boss models. 4)  It comes with a different diameter cv axle to compensate for the increased angle at the differential.

 

5) I had the dealer install the lift with the new cv axles and so far the noise is gone. GM Engineering won't authorize repairs of replacing SU4 axles nor differentials as that doesn't fix the issue. But it seems a different axle part number (oe- different axle design) may fix the issue. So in that perspective it is relevant to know if the Trail Boss axle is yet a different part number with corresponding RPO code.

Your using axle, CV, and differential interchangeably so I am somewhat confused, but I'll try to make do with that I can gather from your post.

 

1)  I apologize, I misspoke when I indicated the differentials were made in Mexico., I should have been clearer and used the term "utilized".  From prior posts over the past 2 years on this website, and others, information has been provided that indicates one of the differentials (not axles) is predominantly used in Mexico trucks while the other isn't. 

2)  I whole heartedly agree, the same manufacturing tolerances are required around the world per given manufacturer.  However, the SU4 and SU5 are completely different designs from completely different manufacturers so there definitely WILL be differences in the two differentials that do not allow for an apple to apple comparison.  

3)  Trail bosses have the same issue because its not the axles, its the differential that's the issue.  If you have proof otherwise, please post.  For your reading pleasure, or if you get bored, please check out this informative post on the SU4 differentials.  I believe you will find some clarity there.

 

4)  The Trail Boss axles are not any different in diameter, its their length, as shown by users who have measured and compared the two.  If you have quantitative proof otherwise that shows them to be wrong (and please tell me its not from the mouth of a dealership technician or parts salesman), please post it since I would much rather admit I'm wrong, learn the correct answer and move forward, than to sit here and give out false advice.

5) If new CV's cured your issue, then you didn't have the same "Jingle-Jingle" issue as others.  The issue is internal to the differential and not related CV length or design.

Posted
On 12/18/2021 at 4:34 PM, AJMBLAZER said:

Neither. That assembly is the CV shaft/axle. You buy it as one unit. The stub shaft is the short axle shaft that goes from the differential to the end of the axle where the Cv shaft attaches. 
 

https://www.rockauto.com/en/catalog/chevrolet,2020,silverado+1500,5.3l+v8,3444633,drivetrain,axle+shaft,10439

 

Understood now.  Your meaning is the mating part of that joint by located within the differential assembly.  That rockauto link has some interesting detail there and honestly, I hadn't thought to reference them as well for this issue.  Based on the image, it looks like there is a different stub shaft based on the front supplier axle code.  The SU5 supplied axle is okay to order just the stub shaft but the SU4 supplied axle requires you to order the half shafts along with the stub shaft. 

 

So it seems there is definitely a design difference between SU4 and SU5 axles.  According the rockauto description, the SU4 has a larger lead in chamfer.

 

I really hope the stub shaft repair on your truck is the fix and that GM Engineering can get off their ass to approve this repair at the dealerships.  Good luck and thank you for the good explanation.

 

image.thumb.png.04c8950fac04e606ca734db51c2ff0a4.png

Posted (edited)

Also, I failed to mention that the "Jingle Jingle" is only experienced in the SU4's, not the SU5's, per GM documentation.

 

Per 

"Some customers may comment on a squeak or chirp noise in 2wd that goes away in 4wd. Some people may also describe it as a metallic jingle, ringing, click or tick. Condition is easiest to duplicate in warmer ambient temperatures, after approximately 30 miles of driving and is barely audible. Technician may notice that the noise seems to be from the front left axle seal area. This information only applies to the SU4 axle in pick up applications AND all utilities.

This condition does not affect durability and or operation of the vehicle but may be annoying to some customers. Test drive the vehicle and confirm the noise is in fact as described above and inform the customer that as soon as a repair is validated this document will be updated communicating that repair to the dealer. "

Edited by Gangly
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