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I have a 2014 Silverado. For some time now it's been making this noise from under the truck. Friends have guessed at it and so have mechanics and we cant seem to figure it out. The guesses I've heard were lifters, rod knock, transmission teeth, drive shaft, and engine misfiring.. moat of which are not the case as the truck still runs well and shifts properly. This noise is also accompanied by a check engine light (Not Flashing) so no misfire... I'm just confused as hell and just want to fix this thing.... also this only occurs while driving at a steady speed only between 1000 and 1500k RPM any faster or slower and the noise goes away.

 

Here's a reference video so you can hear what I'm talking about. 

 

Posted
2 hours ago, Madcow2020 said:

Is the truck in v4 mode when it makes the noise


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No the truck is tuned, it no longer switches to V4 mode. But this noise has been around even before I got it tuned so it's not the tune. Just crossing that out.

Posted

So this may sound odd, and I have only seen it once, I had a 79 Grand Prix that had a noise that no one could figure out for a year. Then one day my starter went out, and the noise disappeared after I replaced it. A nut had came loose on the back side of the Ben did and would cause all sorts of weird noises. Worth a look.


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Posted
6 hours ago, Madcow2020 said:

So this may sound odd, and I have only seen it once, I had a 79 Grand Prix that had a noise that no one could figure out for a year. Then one day my starter went out, and the noise disappeared after I replaced it. A nut had came loose on the back side of the Ben did and would cause all sorts of weird noises. Worth a look.


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But was it accompanied with the check engine? My truck would at times not make that noise and the check engine light is off until the noise comes back.. this is weird as hell...

 

Posted
6 hours ago, Madcow2020 said:

That was going to be my next question. Have you hooked it up to a scanner?


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Yea the code that comes up is P2097 indicating an emissions problem. I'll be honest the truck is straight piped but to go completely straight pipe requires a tune and as I mentioned before it was making that noise much before I had it tuned or removed the catalytic converters. Only thing I haven't upgraded yet is the exhaust manifold. I want to get headers soon.

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