I have a '20 STX SCAB 4x4 with 5.0L and 3.73 and since I bought it new, it has made this like crunching rice crispy noises at the low end of every gear from about 4th-8th. The sound will go away after about 3-5 seconds and the vehicle speeds up so its not at the bottom of the gear. It also sounds to be getting louder since when I bought it. I took it to my dealer, who could hear it when I took them on a drive and they said ford had put out SSM 49761 which addresses this but when I look it up, it does not appear to be what I have. Has anyone had the same symptoms, if so what was the issue, did it cause any problems, and what was the fix. Kind of at a loss here with what to think. It definitely does not sound "normal" as the dealer said. Any info would be appreciated. Thanks!

 

Is it possible to safely record a sound clip? I haven’t heard of this.
Any vibrations? Does engine cold/hot have any noticeable effect? Does it do it in park with engine revving to same rpms or just when accelerating through the gears? Favor any particular “zone?” (Front, right, center, etc)

 

Had this issue with my 427 Cobra when opening the throttle too close to certain non US built cars. Only fix is to keep them away from the intake.

 

I am not sure if my experience was the same but mine sounded like it missed the gear and was trying to catch i would let off the gas and it would catch and the sound would go away. after awhile it started happening a lot so i had to bring it in. They changed out the torque converter which took them 2 months. Move ahead 6 months or so, the sound is back. Called my local dealer and they said it may take even longer this time because of their staffing.

 

Could be vibrations rattling heat shields. Engines produce larger vibration cycles at low rpm.

 

I'll ask, does it do it in 4H or 4A (if you have it)?

 

I tried to get a audio recording from it but its too quiet to catch on my phone. No it does not do it in park, only when in gear and accelerating through the gears at the very bottom end of the gears. No sounds like its coming from the center of the truck just in front of the cab.

I will try that on the way home.


Its not a really loud noise but is audible inside and outside the cab with windows down. It does not do it until I get into around 4th gear around 25mph or so and then will do it all the way until at least 8th then its either too hard to hear or its not doing it at all. That SSM number I think they just made up because I cant find anything about it being relevant on 2020 f150 with 5.0 unless someone can find something I cant. Oh also, never thrown any codes, lights, or messages. Will report back tomorrow.

 

The engine can bog and rattle if you accelerate/drive slowly through some higher gears. This isn’t what you hear tho I assume? If you’re convinced it’s not inside the cab, I’d check your exhaust and anything hanging underneath the cab. Loose clamps, shielding, etc can vibrate at certain rpms and make noise that comes and goes.

 

I put it in 4H (I dont have 4A) and yes it still does it.

I took it to the dealer again this AM and this is the 2nd ford tech there that could hear what is happening and he thinks its something to do with IWE. I personally dont think so but they are going to get all IWE looked at next wednesday. Also yesterday on the way home, the motor started making a constant tap noise from the motor, I got an audio from that but my phone records in .amr so cant upload here. But today when I go start it, sounds completely normal. Also yesterday, the truck started making a fluttering sound from the passenger side of the motor that was the second time in the last week that it has happened and I also got an audio from that. Nonetheless, the crunching noise is definitely not getting any quieter, and is doing it more often than when I bought it.

Starting to question my trucks reliability long term, it only has 14k miles and in the last week I have had 3 new noises come from engine, transmission area. Hopefully the dealer can figure it all out. Will keep you all updated. I may start a new thread on the other "noncrunching noises"

 

Okay, it was a thought. The usual description of an IWE (or something related to it) noise is it sounds like a paint can rattle or a can being dragged down the street. This would be an early indicator. They will grind more and louder as the issue gets worse. Without actually hearing the noise, it was my only thought and yes it could still be an IWE issue even if it does it in 4H. If it did go away, it would have definitely ruled it to an IWE issue.