I hear a knocking sound at the front of the truck.
The noise may be the serpentine belt tensioner vibrating, or the front engine damper is broken and causing a noise. If the noise is neither of these components, then an inspection would be needed to see what the possible cause is; a low thump or knock could be a major internal engine problem. I recommend have a mechanic, such as one from YourMechanic, inspect and isolate the noise, and provide you with a diagnosis.
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