GEN 2 It sounds like a gnome slapping a tape measure around under there.

[blackbird18]

Well, I got the truck back this morning. They said they looked and found nothing. Not IWE. I'll justcwait and see if it happens again.

 

[Oldfart]

Maybe your gnome is done beating his meat??

 

[smurfslayer]

Maybe your gnome is done beating his meat??

are they ever?

 

[06z]

IWE. If it's a metal sounding noise from under the driver, that goes away after you let up on the gas, it's likely the vacuum check valve. It's about a $9 part. I had this repaired on a 2020 Raptor after 26 miles. There's a TSB 19-2252. I took mine in, and after the fix, no more noise. You can test by putting your truck into 4x4A mode. This will make the sound go away. It's an extremely common issue, so your dealer will likely have the part in stock.

I had this exact issue. The dealer replaced all of the IWE components except the check valve. The issue was still there. I bought 2 of the valves and it was fixed. Now I keep a spare in the glovebox.

 

[Oldfart]

are they ever?

Not if they're anything like me!!

 

[TXRaptor]

I had this exact issue. The dealer replaced all of the IWE components except the check valve. The issue was still there. I bought 2 of the valves and it was fixed. Now I keep a spare in the glovebox.

Hold it! You also had a Gnome Slapping sound under your truck? I wonder if it is contagious...

 

[2orque43]

+1 for making me laugh with the title lol

 

[everetto]

I vote for the heat shield theory. Had a similar sound from the rear. Heat shield was vibrating against tailpipe.

I have a "rattle" that to me sounds like a heat shield vibrating against something. It seems to happen most often at slow speeds, like 10-20 mph, at a fairly constant and partial throttle setting, and typically between 1500 and 2000 rpm. If I slow down a bit or speed up a bit it goes away. One time I heard it repeat in a higher gear once I reached the similar rpm. It just feels/sounds like a resonant vibration within a narrow rpm range. I have not yet been able to determine if it is coming from the front or the rear of the truck. I plan on getting under the truck and shaking and banging on everything in sight. It does not sound like any of the IWE vids I have seen and I certainly don't hear it at speeds above about 30 mph.