After the new solenoid and check valve, I sill have the IWE noise. What's the next step to fix this? Do I go with new IWE's and just replace them when they fail or go with the IWE eliminators from RCV? They seem to be very popular with the Raptor crowd...

https://www.rcvperformance.com/rcv-u...150-04-up.html

 

If you replaced the solenoid and check valve and you still get the noise it's time to replace one or both. If you get a vacuum gauge at the parts store you can apply vacuum to each iwe separately and see if one or both leaks down and doesn't hold vacuum.

 

subscribed

 

I wrote a in depth post all about the IWE's quite a few years ago. It should still be relevant to these series of trucks.

https://www.ford-trucks.com/forums/8...ml#post7322441

 

Nice write up! I searched through the 2015+ forums and came up empty, but did not even think to look on the older forums. I understand the system as I had the issue with my 04 and replacing the solenoid fixed the problem. I wasn't sure of the next steps after the check valve and solenoid replacement do not fix the issue. My main concern with this repair is the fact that it will happen again because of the flawed design.

 

The truck that I originally had the issue with was an '04, what I ended up doing was running my own vacuum hose all the way from the solenoid down to both wheels, replaced the IWEs and was all set. There are so many weak points (at least in the older trucks) that if you replaced one part the next part would go, or a crack in the plastic line, etc (on the older trucks there is also a vacuum reservoir that could leak, may be on the new ones too) . I just used rubber vacuum hose from the parts store, bought a pack of misc vacuum hose connectors and put a little bit of silicone on each connection and ran the hose where I could get to it easily down the road and hooked it all back up and was fine until I traded it off several years later.

But I can not stress enough that a good vacuum gauge will be your best friend while working on this.

 

If that's the way you want to go then you can save yourself two hundred bucks. Just unplug the electrical connector from the vacuum solenoid. No vacuum and the IWE's engage. Cuts into your gas mileage a bit since you're now spinning all that front end hardware all the time but accomplishes the same thing and takes all of 30 seconds to do.

 

If you want to get to the bottom of what is failing, get a vacuum gauge and start at the IWEs and apply vacuum to different sections of the system until you find the section or part that is not holding vacuum. It could be as little as a cracked line, which if that's the case, a couple bucks at the parts store for generic vacuum line and connectors and you can replace the section.

 

Nice write up; Reps sent and page saved. I think a vacuum gauge will soon be joining my tool set. My warranty-repair has been solid for 6+ months, but this sure seems like a weak link that will need to be “maintained” as the truck gets older.

 

Here's a TSB straight from Ford.

https://static.nhtsa.gov/odi/tsbs/20...49748-9999.pdf
If it doesn't open, just google TSB 18 2273

 

I considered this thread relevant enough to make it a stickie. Thanks for all the great useful tips and relevant info.

 

This sounds promising to avoid any further damage until I actually repair the problem. Thank you!

 

Unplugged the solenoid and I believe the sound was still there, just not as loud. Could've been me being super sensitive to the sound, so who knows. I ended up trading the Limited in on a '17 Raptor and it has the same problem, go figure. Unplugging the solenoid seemed to have stopped the noise completely. I ordered the YG360 check valve and hope it fixes it. Always an adventure.

 

That YG360 checkvalve is what many of us replaced the OEM one with. Since, Ford finally came out with an updated one that comes with the hoses. Haven't heard of anyone having trouble with the new one, yet.
The part # for the new one is in that TSB I linked to. BTW, it's got a blue colored end on it.
ATTENTION
TSB has wrong part #, here's the one you want.
https://www.tascaparts.com/oem-parts...asy-fl3z3a788b

 

Post #6, Intermittent grinding noise - Ford F150 Forum - Community of Ford Truck Fans
Ford has come out with a new TSB regarding the warmup strategy of the front diff/IWE system. I wouldn't really expect them to do this just by customer request unless there is a problem.
Note, this supersedes TSB 2273.
Don't know to attach a PDF from my computer.