Traveling on the road,heard some IWE noise, like partial disengaged chatter, pulled over, put in 4A, all seems ok. Will it hurt traveling in 4A ? Do you think it could be check valve? Anyone have a pic what I might be looking for ? Thx. Ps, truck under warranty, obviously rather not stop.

 

You can drive it in 4A all the time and it won't hurt it. When I had IWE grinding issue I put it in 4A until I could get them into service and replaced.

 

You can pull the vacuum line to the IWE, and the IWE will stay locked in, since the vacuum disengages the IWE. The half shaft will turn, but the transfer case won't be in 4x4. Plug the vacuum source so you don't have a vacuum leak. It should stop grinding, but you might loose a MPG or two.

I think unplugging the electric on the Vacuum solenoid will accomplish the same thing. No vacuum will make it to the IWE's, and they will stay engaged.

 

https://static.nhtsa.gov/odi/tsbs/20...81917-0001.pdf

 

Yeah, either drive in 4a or unplug the electrical connector at the vacuum solenoid. Unplugging the electrical will cut the vacuum. If you pull a vacuum line you'll need to plug the port. Nothing added to do if you pull the electrical. Just be careful not to break the plastic locking tab for the connector. Take your time and you should be okay.
Without vacuum or electric the hubs stay locked. Driving in 4a engages does the same, however it keeps the transfer case 'on' all the time. My vote is for pulling the electrical, second is to drive in 4a. Obviously it will make a bit more noise so if you aren't aware of that, don't be alarmed if you hear the groaning sounds while in motion -its just the moving parts under your feet that are usually not moving.

 

I haven't brought mine to the dealer yet out of fear that it won't do it for them. My dealer is 50 miles away, so I can't waste a day on that. Mine is the same, it does it in the same spot on my to and from work!

 

I replaced the checkvalve, never has done it since.

 

Follow up to my quest for an answer - this was from a dealer in a nearby city to me that has a good repuation. I'm happy they are at least acknowledging the issue although it appears there is still no know root cause

"The noise you are describing sounds like an IWE (Integrated Wheel End) issue. They are very common in F-150's because of the way the 4WD is set up.

Typically, 2020 models and older were easier to diagnose because the 4WD system was controlled by vacuum allowing us to check IWE's, lines and check valves for possible leaks causing the IWE to partially engage into the back end of the wheel bearing, leading to undesirable noise. These vehicles had a technical service bulletin for the concern.
      
2021 and newer F-150's IWE system is controlled electronically, making it more difficult to diagnose without codes present. At this point in time Ford does not have a Service Bulletin to address this concern and we have no idea why the electronic system is having the same issues. We have been able to duplicate the noise the same way you were able to, Switching between 4WD-2WD and driving. We've replaced the IWE's and wheel bearings on the newer models to correct the concern, but we are not entirely sure why the IWE actuators have had difficult engaging/disengaging on the newer models as the issue was supposed to be corrected by switching from vacuum to electric operation.

As far as damaging drivetrain components, the only damage that is done is the IWE gear itself and the backside gear of the wheel bearing. They grind together due to partial engagement. This does not affect the integrity of the wheel bearing, but after an extended period of time, it can affect the ability to lock the affected front wheel end into 4WD when commanded due to those gears being rounded off.

The vehicle being a 2023 with low mileage, I would get it diagnosed, and order parts to correct the concern, We usually don't have the parts in because of availability issues with the wheel bearings and end up ordering them per affected vehicle. Coverage for these components falls under your powertrain warranty (5-Years, 60,000miles) or bumper to bumper (3-Years, 36,000miles). The repair will fix the issue for right now, but there is a possibility that it can return in the future as we have not received any bulletins from Ford regarding the IWE problems with 2021 and up F-150's at this time."

 

Thanks for that update, disappointing for sure. Good luck getting yours resolved.

 

New here. Been trying to figure out this grinding for a few weeks. Based on previous threads, I first replaced the IWE check valve assembly. Still had the noise, so replaced the solenoid next. Thought it was fixed...then later that day heard the grinding again--always as I'm braking/decelerating. Only in 2H, and goes away in 4A and when solenoid is unplugged. What next steps do you guys recommend? Dealer?
Sorry--meant to post--2015 King Ranch