I have a 2022 Silverado LTD Custom Rally Edition with the 4 cyl, 8 speed with about 2400 miles on it. Recently it started doing a knock noise which sounds like from the passenger side rear. I can’t really tell if it is in the cab, the bed or under the truck. It sounds just like someone knocked on the bed of the truck.

I had it at the dealer for the notorious rumble issue (which was a minor shudder) and they thought the knock was the plastic rear wheel well liners I have it. They adjusted them, but it still does the knock. Strangely, I can’t make it knock, it is pretty random and usually within the first couple minutes of driving. Also, I’ve heard it at a stop and when I’m driving.

I do have 2 car seats in the back, so I thought it was the seat anchors, but now that it does it when I’m stopped I can’t see why it would be the seats for the kids. I also swapped the side the car seats are on, and the knock is still on the same side, where if should have reversed sides by moving the car seat.

it seemed like it started around mid-June when it started getting warm out, if that has anything to do with it. Dealer is clueless to what it could be.

I also tightened the jack that is under the seat.

Has anyone had this before? Any ideas what it could be?

 

I recently got a '22 RST and I've noticed the same sound from the back passenger side as best I can tell. I assumed it was little rocks being thrown into the wheel liner but haven't really got a chance to investigate further.

 

Is it hot where you are? Now im pretty sure mine is the plastic spoiler. I found another thread on it on another site. I just heard it before when I was outside (about 85 degrees here and sunny) and the truck was off and sounded like the spoiler.

try flicking the bottom gap the spoiler, it may be the sound you’re hearing too.

now that I seemed to have found the noise, I have no idea how to fix it lol. maybe something to shim it. I also don’t have a sliding back window so yours may be different.