2016 F150, platinum, fx4, 2h/4a/4h/4l with locker rear. Started with what sounded like front hub noise, got the truck in the air and realized it was my front drive shaft. The u joint from the transfer case to the front dif has gone bad. I took it to ford who couldn't diagnose the problem but strongly suggested it was from the lift kit ( even though they installed it). The issue is my front drive shaft is always engaged, iwe's are not engaged, and all functions of 4WD still work but now they say I need a new transfer case and front drive shaft that they can't get for another 2 to 3 months. I'm here to see if anyone else has had an issue like this or if anyone has ideas on what else to check that could possibly be an issue. I'm just not good with "we're not sure what's wrong so let's replace it..."

 

Nothing? I'm the only one?

 

So the transfer case is basically stuck in 4WD? Does it shift into 4 low?

 

Yes, 4wd works through all the gears. Just won't disengage the front drive shaft.

 

Since you have 4A, the front drive shaft will rotate even in 2H, it's the nature of the beast. That TC will "leak", for loss of words, thru the clutch. I'll attach a video that explains how this works.
Are you lifted or leveled? There is a difference. If leveled, has little to do with the angle of front driveshaft.
You may want to take truck elsewhere that knows what they're talking about.
It may be more than just the front ujoint, that front pinion bearing has had a tendency to go out due to factory installation.
Anyway, here's the video;

 

This was my understanding of how the system was supposed to work. But the Ford service advisor was adamant that the drive shaft should disengage in 2 high. I thought maybe I misunderstood how it works so I just assumed I was wrong but I don't think I'll be taking my truck back there again.

 

You have to understand that all "service advisors" are not created equal. They don't even have to be mechanically inclined. If you happen to run into one with good mechanical knowledge, you're golden. Used to be many SA's were olde mechanics, and actually made more than a mech. I don't know what the pay difference is now, but I suspect it may be the opposite.
The drive shaft IS disconnected as far as any actual engagement, but with the TOD, 4A TC, it works just like that video.
Time to go elsewhere, or hope the mechanics know what they're doing.

 

Hey Dukdwn, did you find the fix for this? My 2016 f150 is doing the same and also has a lift kit. I have verified correct IWE operation.

 

Welcome!
..