As usual, I search and ZERO LINKS come up.
Anyway, my 4wd system has been making noise and I'm running in 4H.
I want to troubleshoot the system. Anyone have a link to a procedure?
Which MightyVac do we like? I'm thinking the higher end one, which also has pos pressure.
Thanks!

 

Here's the TSB Ford issued a while back, it's still relevant. https://static.nhtsa.gov/odi/tsbs/20...71859-0001.pdf
What sort of noise are you getting?
Oh, and DON"T drive around in 4H, 4A is OK, as well as pulling the power at the solenoid to get the IWE's engaged, in case you're getting grinding, just don't put TC in 4H/L

 

I would drive slowly between 2-15mph listening carefully and then switching between 2wd and 4A....do not shift on fly to 4H...my iwe blew out shifting into 4H when backing up and then going forward and shifting into 4H.when out camping a few yrs back...pita.

If sound is varying when 2WD and 4A, then just first swap out the hose/check valve, it's like $20..FL3Z-3A788-B

if still issues then can start chasing down leaks. This dude has a nice video on IWE.

 

Woops! Thanks, I meant 4A. I've been in 4A for a few months now.

I'm getting a rotational grinding/hum that goes away as soon as I put it in 4A.
I know I have to check vacuum and the checks. I plan to buy the MityVac tool. I just need a procedure. I'll check the TSB, Thanks!
TomJV

 

DO NOT use that video, that guy just ruined a brand new IWE, by not aligning the teeth before taking an impact to the spindle nut. DO NOT use an impact either!!!! And, after aligning teeth, torque that nut down to about 27-30ft/lbs.
Here's a video from a guy that actually isn't a hack, his videos are well done, and spot on. I recommend this one, the year is different than the OPs, but it's all the same.
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Here's another pretty decent one as well.

 

that was perfect! Thanks!

 

I'd betcha most of the vacuum pumps on site here are MityVacs. Decent price at Harbor Freight, especially for something you won't use everyday.
Anything you might need, just ask.

 

If you have a 4A truck then Ford will just bypass the IWE system and leave the hubs engaged, because they have no reliable way to fix the design.

 

So, I bought the MityVac Silverline tool for $85 on Amazon. NICE tool. Heavy duty, all AL construction. Nice big gauge.
I used the tool to evaluate the hubs. I jacked each side, one at a time, removed the vac hose and hooked up the MityVac.
I tested the hubs engaged and disengaged with the tool. Perfect.
I tested the hubs engaged and disengaged with motor running. Perfect.
CONCLUSION: It's a wheel bearing.

Bought the wheel bearing and installed it. Easy enough job. I take my time, took me about 2 hours.
Test ride? Sounds better, but not perfect. Sounds "different". I'm now thinking I'm gonna do the other side.

Notes:
When I removed the bearing, the sealing surface was really rusted. It took me a long time to get it clean. I applied a thin coat of Permatex to it when installing the new part. I'm surprised there isn't a gasket there.
There was some gunk in there, but nothing crazy, no metal shavings.
The old bearing is sloppy, but not terrible.
The new one was very tight and also dry. I applied grease to everything and worked it into the bearing as best I could.
The axle spindle has a blue ring where the bearing sat, so it was probably running hot. Or is that normal?
It was definitely cool to be able to test the IWE and SEE it working and holding vac.
Before I did this, I felt compelled (noise) to shift into 4A as soon as I started moving. Now, it's about 1/4 as bad. I'm thinking it's the passenger side bearing. The truck has 92K on it, so it's not so unusual that bearings need attention.

Some folks SAY, bearings such as these should be replaced in pairs. Makes sense. Others say, if it ain't broke, don't fix it. That ALSO makes sense.

I bought the better tool because I didn't want the plastic one and it does pressure as well as vacuum.

I'm going thru all this because I want to take a trip and NOT break down away from home.

 

Good, you're making headway! That blue ring is normal, comes from the factory that way.