Hey all,

Have a (new to me) 2020 Ford F150 Platinum with a 3.5 turbo w/ 51K. I got new tires a few months back and noticed a slight rubbing/griding when I start to slow down (30mph or less). At first I thought the front rotors were bad, took it back to Schwabs and they did a "full inspection of the brakes" and couldn't reproduce the sound, checked bearing though and said everything is in order. I reproduced it pulling out of the lot and they thought it could be warped rotors after that. I do get slight feedback, similar to bad rotors. It goes away when I shift it into 4H (which leads me down the IWE path). Just for kicks I replaced the check valve and hose. Had vacuum when pulling it off. It does not make the sound every time I stop, it isn't consistent, but I usually can reproduce with additional drive time. I do not feel or hear the noise when stopping from a high speed. I'm not the most mechanically inclined, but if there is a video or diagram I will dive in.

I'm going to pull the wheels today and verify I don't have a rock stuck somewhere. Any additional suggestions on what to check?

 

Drive it a few days with it in 4A. That will keep the iwe's engaged. Perfectly fine test, if sound goes away and stays away, you have iwe issue. PS: Fords warranty fix is to permanently engage them.

 

Please let us know what happens. I have almost the same story but mine makes a scraping noise no matter where the drive select is at all speeds above 5 mph. I have vacuum from of my solenoid but I don't know how much (I don't have a vacuum guage) but my CV shafts turn with the tire when it's in 2WD engine running with front jacked up in the air. I dropped it off at the Ford dealer this morning. We'll see what they come up with. It's a 2017 F150 3.5 eco. 114k miles.

 

Ran some errands this morning in 4A. Didn't hear or feel anything and I ran the same route I always hear it on. I will keep you all posted.

 

Get a vacuum gauge from Harbor Freight or online. I thought this video was very good out all the other videos on YouTube and easy to understand on troubleshooting

 

Thank you so much for the video, It is informative.


 

You can do all the troubleshooting you want, but Ford can't fix the IWE system on 4A trucks and their fix is pull and cap off the vacuum lines so the hubs are engaged all the time, They newest F150s with 4A Ford did not even pretend IWEs were going to work and did not install them at all.

 

Seriously? First, I thought Ford had issued a superseded TSB that went away from the simple "fix" of plugging the IWE vacuum lines. Second, if what you say is true, all the newer model 4x4s (upper trim levels with TOD transfer case (4A option) are constantly turning the entire front driveline--hubs, half-shafts, axles, ring and pinion gears, front driveshaft, CV joints. Hard to believe they'd go to that design that opens them up to all the warranty issues on those parts, not to mention the seals and bearings that would be subject to wear!

Say it ain't so!!!

 

Yeah I don't believe that. Fords fix is to replace the IWEs..

 

Just an update. Drove around in 4A, all seems fine minus feeling sluggish, but it is what it is. I did replace the solenoid, (on top of a new check valve and hose) and have tested out 2H. I wouldn't say it solved anything, but I wouldn't say I hear/get the feedback as much. It only happens at low speeds when applying the brakes to come to a stop, never happens coasting to a stop, which has been he case all along. I'm going to pull wheels and rotors myself and see if there is anything going on. I'm hitting my mechanical limit (still might grab a pressure gauge) and will schedule an appointment with the dealer if nothing found.