Dogdad

I’m willing to bet you get the return of the clunk…mine went away with new leaf springs installed..but came back with in a week..

When he was shaking the truck..you were hearing axle play…you need to go educate him.

There’s a thread on the starter issue if you do a search.

When you move the back of the truck by pushing and pulling on one of the rear tires , you can hear a clunking noise but that is actually normal as it’s called axle play. But what you’re hearing Is 99% because of your leaf springs. Let us know how it works out.

Probably not your tire but the leaf springs..get the Spring Things… $40 fix

Recall on infotainment system??

Grease just collects dirt and grime in them. Just install the $40 spring things, a 10 minute fix and it’ll solve the issue.

Did you Jack up truck where tires were off the ground to install them and couldn’t fit them in over the grey plastic ones?

Look at my pic of my install . Leave the grey plastic piece there. Install on top of it.

Glad to hear.. it’s unfortunate that GMC doesn’t do this for us that buy their trucks.

It will solve the issue

When I started hearing the clunking noise from inside my truck while going over a driveway curb and such, I thought it was a loose spare tire or tailgate making the noise. Then I discovered what I thought was the same noise by pushing the top of the rear tire back and forth and thought wow..I’ve got problems with this new truck. Brought it to a dealer ship and showed the shop foreman . He told me about axle play and told me I was hearing the leaf springs and confirmed it after driving the truck. They actually replaced the leaf springs and a week later the clunking was back. Then after researching the issue I came across the Spring Things, brought them to the dealership where he actually installed them. Haven’t heard the clunking since which has been 7 weeks. He also told me the dealership had been installing rubber bushings they made and GMC told them to stop. Anyway, out of curiosity, I just went out and shook the tire as we discussed and yep…noise is still there from the axle play. Thank goodness we don’t hear that in the trucks.

You are actually incorrect about rocking the tire and reproducing the sound.. What you’re hearing rocking the tire is called axle play . It’s normal on all trucks. Go to a dealership and rock the tires on any new truck..you’ll hear it. The clunking is the leaf springs.

Spring-things.com

And no, it’s not normal

2021 Sierra

I’ve read that applying grease is only a temporary fix and collects dirt. Try the rubber bushings.

I brought mine in and had the springs changed. Clunking noise came back within a week. Finally installed the Spring things and it solved the issue.

Buy the Spring Things .. easy fix and solves the issue.

New 21 with 1200 miles. Had to have it towed in the dealership. Shop foreman thinks it’s fuel related but won’t look at it till tomorrow. Video of what it’s doing and I’m assuming this is what most are experiencing? …….. I made a video with the floor mat keeping the truck from starting. This site won’t let me post it…but if you start your truck with foot on brake and gas pedal down…same effect.

Slipped the mat in front of the gas pedal by not paying attention. If it’s a fluke , I have no problem reposting that the issue happened without the floor mat scenario.

Any more issues since the floor mat correction?

No more start issues since the floor mat causing it?

Had my 21 Sierra with 1200 miles towed to the dealer Saturday because of the non start issue. However, Saturday night I got on this forum and read through the post. One thing that stuck out to me was the few post regarding floor mats causing the issue. It just so happens that Saturday afternoon after enjoying a couple of cigars, I came out to my truck and pulled out my floor mat ( GMC) to shake it off. After installing the floor mat and getting in my truck is when it wouldn’t start. So I got to the dealer earlier this morning and went and looked at my floor mat. Well damn, it was covering the gas pedal. I corrected it and started right up.. with me laughing and shaking my head. I told the shop foreman this and he laughed. It wasn’t the first time he’s seen this. He said you can’t press on the gas pedal when starting as it shuts down the fuel pump.. a GMC safety feature. So check your mats and make sure you’re not pressing on the gas pedal while starting.