So my CPO warranty is about to expire and this noise just started. Gonna try to get it in before it’s up but if they can’t figure it out before then I’m on my own. 2013 F150 STX 5.0 4x4. I started hearing this clacking rattling kind of noise when I’m driving down the road, can definitely hear it under light acceleration with windows down especially next to wall or other object. And seems to happen in 2wd and 4wd. May be intermittent but can’t tell as some conditions would make it difficult to hear. It sounds like it’s coming from underneath. I put the truck on jack stands and spun the wheels and axles and shafts by hand and put it in drive 2wd and 4wd couldn’t recreate the noise in the air. Only thing I heard was from front left axle kind of sounded a little marbley but I’m not convinced that’s what it is. Checked to see if anything was loose, found nothing. Any one experience this noise or have any good ideas? Link to noise

 

Very hard to tell from the video. If you live in an area with snowy winters, I’d suggest checking the heat shield clamps. There’s one that is known to rust and start rattling.

I developed a bad rattle that sounded like a rod knock on my 14 5.0, I checked the heat shield clamp but I live in the south and it was still solid. Turned out to be a bad cat and a $400 fix. Just some input, video is rough.

 

I know I tried my best with the video and uploading it made it worse I made a bunch and this was the clearest one I have. I’ll post others. I live near Phoenix AZ so absolutely no snow here haha. I did crawl around underneath and couldn’t find any loose shields, I banged on everything I could and found nothing unfortunately. A bad Cat wouldn’t sounds reasonable due to the lack of rhythm this noise has.

 

Sounds like the IWE(s) are grinding. Does it go away when you put it in 4H or 4A?

 

Unfortunately it seems to be the same in 4wd also. Any way the IWE components fail and would make this noise in either position?

 

not saying it’s a cat, but when my cat went, it had zero rhythm.

 

Yes, if they were one or both were broken enough but, it also doesn't rule them in either. If it went away, I would say it had something to do with the IWE(s). Can't hear it clearly enough but, the most common description of the IWE grinding is it sounds like a paint can rattle or a can being dragged across the pavement.

Does it change with speed?

 

it does increase frequency with speed. I’ve seen videos of people with iwe issues but I don’t think the noise I’m getting is as gnarly as the videos I’ve seen. It’s more shuttle. Here’s another video I don’t know if it’s any clearer.

 

Not much clearer. The wind noise is drowning it out. Can you hear it from the inside?

I'd go look at heat shields like 2014fiveoh suggested. Look for anything loose, rocks on top of them, etc.

Also, check the connectors on top of the catalytic converts to see if they are loose. Obviously, after the truck has cooled off.

I'd also go do a visual inspection of the all the lines from the solenoid down to each IWE. Check for any cracks in the line. If the leak is enough you may even be able to hear it while the engine is running. If you have a way to put a vacuum on the system (do do a lot as it doesn't take a lot to disengage the IWEs) and then hold it to see if it holds and to see if you can hear any leaks since you won't need to have the engine running.

 

Yeah I know the wind is a pain in the *** I haven’t heard it in the cab, just with the windows down. I’ll definitely crawl back underneath tomorrow and recheck everything and I’ll check out the IWE system as well. I just hope it’s not coming from any engine internals or trans or transfer case. Anything else I can love with the cost lol. Hopefully if I can’t find anything this weekend the dealer will be able to get it in and look at it before Wednesday