Knocking noise in back end of 2018 Chevy Silverado LTZ

StrongSilverado18 · July 21, 2020

Hello to all my GM people! Can you please give me some insight into why my 2018 Chevy sounds like the back end is always grinding/knocking and just flat out making a ton a noise you would not expect to be there from such a new truck. I bought this thing brand new and I have heard some rumors that these trucks are known for this issue. Any solutions? Feedback?

Appreciate yall!

CamGTP · July 21, 2020

Mines makes noise on uneven changes like going up a driveway, doesn't bother me. Probably just the leaf springs or something making the sound.

Jmanson6262 · July 21, 2020

Cam, can you feel yours when it pops n knocks? Mine almost feels like bad struts but in the rear. I know the suspension is good as I only have 33k on the truck and don't really use it rough. It drives me nuts hearing it.

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CamGTP · July 22, 2020

Sometimes yes and sometimes no. Kinda just depends on where/what I am doing. I even wonder if part of the noise in the bed flexing/moving and the tailgate getting pushed/moved causing the noise.

Jmanson6262 · July 22, 2020

I thought that too. I checked all my body mounts just last week. It wouldn't bother so much if it had always done this but it only started a few weeks ago. I have read that some have thrown rubber in the leaf packs. Might give it a try n see what happens.

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StrongSilverado18 · July 22, 2020

18 hours ago, jamisonericksen said:

Cam, can you feel yours when it pops n knocks? Mine almost feels like bad struts but in the rear. I know the suspension is good as I only have 33k on the truck and don't really use it rough. It drives me nuts hearing it.

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Same! I am taking it tomorrow and found a comment on youtube from a guy who said he RETorque everything in the back and it worked. So we shall see.

Jmanson6262 · July 22, 2020

Same! I am taking it tomorrow and found a comment on youtube from a guy who said he RETorque everything in the back and it worked. So we shall see.

Strong, let me know what your outcome is on this please.

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StrongSilverado18 · July 22, 2020

2 hours ago, jamisonericksen said:

Strong, let me know what your outcome is on this please.

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Yes, will do! Have a good day

Jmanson6262 · July 22, 2020

Yes, will do! Have a good day

You do the same, thanks.

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NITTY · July 29, 2020

Not sure if same sound or not but after having my truck a month I had the bed sprayed Line-X and Krown Coating Undercarriage. Shortly after I noticed a "knock" in the rear. Had somebody bounce the back while I stuck my head in the fender well and it is the leaf springs on both sides. I haven't tried to diagnose further but I was assuming it had something to do with the extra weight (wouldn't think that would be a problem) or the Krown Coating with collects a lot of dust and gunk. I was going to pressure wash the leaf springs real good and see if that does anything but I'm not hopeful.