slow speed suspension clunking

BlueRose · October 8, 2020

On 9/17/2020 at 6:51 PM, Kiznolby said:

Thank you. What is the correct TSB #? Saw one earlier in this thread but also saw a post that said that one didn’t apply to this problem...

I showed the dealer the bulletin and he said the ones online available to the general public are not true. Im like WTF! Dealer said that nothings wrong with my freaking brand new 50k truck.

Kiznolby · October 8, 2020

16 hours ago, BlueRose said:

I showed the dealer the bulletin and he said the ones online available to the general public are not true. Im like WTF! Dealer said that nothings wrong with my freaking brand new 50k truck.

lame - sorry to hear this. i know it's annoying as hell. as i mentioned previously, my 2017 1500 did this same exact thing and i just put some rubber sheets between the leafs and it fixed it just fine. i think another guy posted that he used a cut bike tube and that there's a you tube video of it - you should be able to find it. i used a rubber-like shelf paper/covering that i found at home depot and that worked fine too. good luck to ya.

BlueRose · October 8, 2020

1 minute ago, Kiznolby said:

lame - sorry to hear this. i know it's annoying as hell. as i mentioned previously, my 2017 1500 did this same exact thing and i just put some rubber sheets between the leafs and it fixed it just fine. i think another guy posted that he used a cut bike tube and that there's a you tube video of it - you should be able to find it. i used a rubber-like shelf paper/covering that i found at home depot and that worked fine too. good luck to ya.

i know i just bought some, the bulletin shows the dealer installs some rubber inserts and re torues the U bolts, kinda dont feel like dealing with them anymore. Whats the use of complaining?

Spyderwebb · October 10, 2020

On 10/7/2020 at 11:11 PM, BlueRose said:

I showed the dealer the bulletin and he said the ones online available to the general public are not true. Im like WTF! Dealer said that nothings wrong with my freaking brand new 50k truck.

That's bullshit, my statement from the dealership reflects the exact same Service Bulleting as the one this post shows. I am very pleased with the repair...... the noise has been completely eliminated!

Truck's rear suspension seem tighter and quieter!!

I'd insist!!

HamSilverado2020 · October 10, 2020

I have the same issue with my 2020 Silverado 5.3L Custom

Had it into the dealer three times for this issue

My buddy is the lead mechanic at one of the dealerships so before taking it back in to the service department where i purchased it, I took him for a ride

he told me they all do it - sorry $60k truck should not be making any noises - he did mention to me that the fix was to lubricate the springs

First time lubricated the springs was the answer - Wrong lasted three days and clunk was worse than ever

Second time they replaced both springs and tightened the ubolts- lasted one week and noise was back again - albeit not as bad as the first time

Third time replaced the shackles - drove it for one week with no issues - and now its back

Waiting to hear what there answer is going to be this time

While in the shop they gave me a 2021 GMC as a loner - it had the same issue

This obviously is a GM design flaw

GM engineering needs to get involved here - i get it that a little noise is one thing, but when it sounds like the back end of my truck is falling off, that is not acceptable

Keep bugging your dealership - do not take no for an answer or the response they all do this - yes they all do it because it is a design flaw

This is not acceptable and extremely frustrating

I have been a GM person all my life and I am losing confidence in them

My 2011 Silverado to the day i traded it in for the 2020 did not make an ounce of noise from the back end,

torquerules · October 26, 2020

2020 3500 dually, long story short, it's fuel slosh causing the thump. Either the slosh hitting the top of the inside, (doubtful) or the shift in weight causing the tank to nudge one of the cross members.

Donnie Summers · October 26, 2020

Jus wundering, Did anybody bother to check the torque of the leaf spring bolts, My truck had less that 500 moles on it and I checked mine due to another thread and they were less than prolly 40 foot lbs, Torqued them to like 85 and I am not having any issue with the rear end noise....

Thepirate · November 12, 2020

Have 5300 miles on a 2020 2500HD Duramax, I’ve owned 7 others none had this issue. I checked the shocks, spare tire and exhaust mounts and that’s not the issue, I haven’t yet taken it to the dealership so let’s see what they say sounds like we’re all having the same problem

ericarenee · November 13, 2020

This issue is not just on the high end trucks. We have a 1500 2020 WT with 4.3 v6 that does this something awful. Luckily I have a great relationship with a local dealer. (did not buy the truck there they did not have it in stock.grrr) . Will have them to address this and another annoyance issue at first servicing.

Other then that I love the truck thou its 3 months old and only drove it 2k miles

wahoowad · December 14, 2020

My 2019 Trail Boss Z71 does this clunking a lot. Sounds like the the whole axle is bouncing around. I can rock the bed by hand and hear it. Makes a new $50k truck sound like an old piece of ******.

Taking it back to the dealer soon. The first time they said they could not replicate the issue so I drove around for 8 months like this. Hoping the TSB will help and the fact I can now shake the truck and hear it.

JDCrae · January 7, 2021

Apparently a guy invented a product to take care of this called spring-things. If the dealer isn't able to fix the problem on my 2021 silverado custom 1500 with 500 miles that is doing it, I will give this 30$ kit a try. Certainly shouldn't have to on a 47K truck, but the noise is driving me absolutely insane. Thought it was my trailer hitch rattling so bought a tightener, but sure enough, it does it still. Same kind of sound though so clearly metal on metal contact. Leaf springs just need more isolation from each other and GM clearly went cheap with super thin isolators, and their aligning pins are too sloppy allowing excessive lateral movement. Honestly a simple fix, and the manufacturer of the part, which is not GM, needs to supply all new properly made parts .

Tony1023 · April 8, 2021

I'm having the same issue took it to one dealer they said it was A messed up tie rod they fixed same thing happened so I took it to another they said it was the rear leafe springs they replaced them over 2k later noise is still there this is a 2019 silverado smh!! It's sucks driving a "new truck" and it sounds like a pos!! Hell my ranch truck is a 03 and doesn't make no noise and it has over 300k miles on it lol smh that's pathetic and the worst part is they don't what the issue is and trucks are expensive af nowadays

im4snow2000 · April 25, 2021

I think I solved this problem on my 2021 1500 Elevation. I heard no noise when the truck was new, but with more miles, now I'm at 4k, the noise became more prevalent. To summarize, the problem was worse (most obvious) at slow speeds, when turning, and when the truck was on an angle (ie, the road had some slope). Sounds like something is loose. Have someone shake the bed of your truck side to side to recreate the noise, and visually observe the leaf springs, especially at the leaf spring insert to see if this is the source of your issue, to see if this is the root cause of your issue.

With much help from this thread, I added some roughly 1/4" rubber to the leaf springs, sitting on top of the leaf spring insert. Refer to TSP 19-NA-129 for pictures of the factory leaf spring insert. This TSP notes to install new rear leaf spring inserts. These are thin plastic (I think plastic) used to separate the metal of the leaf springs. In my case, when you shake the truck side to side to recreate the noise, you can see the individual leaf springs moving side to side, and the noise seems to originate from the upper leaf spring rubbing against the insert. Rather than replace the insert, I simply added a piece or rubber on top of the insert.

So far the noise appears to be gone. Whatever material the factory insert is made of doesn't work well with the upper leaf spring that rests against it....resulting in noise when the leaf springs move laterally (ie, rounding a turn on a sloped road surface). At least this appears to the be case once the truck gets some miles on it.

Edited April 25, 2021 by im4snow2000

Dogdad · April 30, 2021

On 4/25/2021 at 6:03 PM, im4snow2000 said:

I think I solved this problem on my 2021 1500 Elevation. I heard no noise when the truck was new, but with more miles, now I'm at 4k, the noise became more prevalent. To summarize, the problem was worse (most obvious) at slow speeds, when turning, and when the truck was on an angle (ie, the road had some slope). Sounds like something is loose. Have someone shake the bed of your truck side to side to recreate the noise, and visually observe the leaf springs, especially at the leaf spring insert to see if this is the source of your issue, to see if this is the root cause of your issue.

With much help from this thread, I added some roughly 1/4" rubber to the leaf springs, sitting on top of the leaf spring insert. Refer to TSP 19-NA-129 for pictures of the factory leaf spring insert. This TSP notes to install new rear leaf spring inserts. These are thin plastic (I think plastic) used to separate the metal of the leaf springs. In my case, when you shake the truck side to side to recreate the noise, you can see the individual leaf springs moving side to side, and the noise seems to originate from the upper leaf spring rubbing against the insert. Rather than replace the insert, I simply added a piece or rubber on top of the insert.

So far the noise appears to be gone. Whatever material the factory insert is made of doesn't work well with the upper leaf spring that rests against it....resulting in noise when the leaf springs move laterally (ie, rounding a turn on a sloped road surface). At least this appears to the be case once the truck gets some miles on it.

Sorry for a dumb question, but do you have to undo bolts to slip in this rubber piece? I just had the leaf springs replaced on my new 21 Sierra with 300 miles on it and still have the clunking noise. Looking today I see the inserts are indeed plastic on the new springs .

GeorgiaRST · April 30, 2021

Add me to the growing list. 2021 RST z71 4WD.
I purchased it two weeks ago and noticed the clunking backing out of my driveway on the 3rd or 4th day. It’s louder now and gravel roads are awful. It’s non stop on uneven roads.
Scheduled a service appointment.
At that point I went ahead and opened a claim with their customer care department because I had already read this thread and told them I was prepared for the service department to give me the run around.

I called the dealership got passed back and forth and then the service manager told me on the phone the rear ends are just noisy and there is probably nothing they can do.

I took it in and they did nothing, said it was fine and normal for these truck models.
I laid it out that is an embarrassment for GM to have 50-75k trucks that clunk around like the u joints are busted. I also gave them the TSB and referenced it. They said it’s not pertaining to 21s. He said his 2020 2500 does it too. That may be fine for him but not us.
Called the customer care person and expressed displeasure again. Told her I have lost all trust in the dealership since they won’t do anything. Provided her all the information I have for repairs. Contacted another dealer and they said it was normal as well and the service managers truck makes those noises too! Imagine that! I then told him there is absolutely a fix for this and referenced the TSB. He told me the factory installed components are different on the 2021s compared to the 19-20 models. He did finally say they would look and see if they could fix it but I told them no thanks at that point. I then had a certified chassis mechanic drive and check it out and he thinks it’s the springs as referenced by other posters as well. I have an open complaint with GM now as well.
She is trying to get me to come back to the dealer to look at it again and ride with several people. I don’t have any faith in that options because I’ve already got the run around twice. I have a hard time believing all the new 19-21s sound like this. I talked to a steel company with a new fleet of them and he said theirs aren’t making noise. Spoke to a few other people

that said they don’t notice any noise from the rear end.
I ordered the spring things kit to fix myself but I’d rather not since I just bought an nice new truck so I wouldn’t have to mess with anything did awhile.

has anyone else had any success with the TSB dealer repair?