Belt knocking sound

[p1zaul]

2015 Denali with around 100k miles developed what sounds like engine knocking but seems to be coming from the belt. The belt itself seems to be the correct tension. Is it possible one of the things the belts is attached to is loose?

Link to video

New video by Paul Terrigno

photos.app.goo.gl

 

[Doubeleive]

2015 Denali with around 100k miles developed what sounds like engine knocking but seems to be coming from the belt. The belt itself seems to be the correct tension. Is it possible one of the things the belts is attached to is loose?

Link to video

New video by Paul Terrigno

photos.app.goo.gl

that's not the belt making that noise, it's what the belt is spinning. you could try taking the belt off and spin things by hand, whatever is loose or noisy is the source of the noise.
hard to tell from the angle of your video but I would suspect perhaps the water pump or a tensioner. the vacuum pump is also behind there with it's own belt
if it is the water pump do not fret they are modular on the k2"s and the pulley portion can be replaced easily.