Whirring/whooshing sound in 4a?

[Badgertits]

Not sure whether this is “normal” & I never noticed it until now, but been raining heavy last few days & had left truck in 4a, was nice out this afternoon & had all the windows down going down highway & realized truck was still in 4a so I switched it to 2wd & immediately noticed was quieter overall.

Put it back in 4a & sound returns - only under throttle. I guess it could be a bad bearing noise but would still hear that in 2wd, it’s a whirring/whooshing air type sound, not a grinding whining typical mechanical issue sound

Literally opposite of what an IWE issue sounds like- it comes on in 4a under throttle goes away in 2, iwe seems like it’d be the opposite

I know the front hubs are engaging as I can feel the front biting when it was wet out & did a little off-roading last week as well.

Any ideas?

On the passenger side I noticed a little bit of weeping at the axle seal - which I know is common- but my truck showed this from day 1 & it was initially a little wet when I first got I figured maybe overfilled and/or weeping stopped on it’s own- you. Can tell from this pic, certainly doesn’t look like it was weeping anytime recently, also I heard this from the driver side (Altho may also make it on passenger side but can’t confirm yet)

Any ideas?

Would post a vid but not sure how

 

[Badgertits]

Not sure if this is going to be decipherable or not but the noise is faint sounds almost like it’s just more wind/tire noise like worn down tire, but you should be able to tell the difference 1 from the other, it’s faint - but can also kinda hear right @ the end of the first vid when I let off throttle gets a bit quieter.
View attachment IMG_0739.MOV
View attachment IMG_0740.MOV

 

[BoostCreep]

I just noticed this exact same thing on the highway today, except neither of my axle seals have any seeping or leaking. A couple days ago I did just discover my front diff pinion seal is leaking, so now I’m hyper paranoid/sensitive to all sounds. To be honest, I think it’s just extra nvh from the front driveshaft, diff, and cv’s rotating. It’s a lot of extra heft moving around quickly up there compared to 2h.

 

[Solidred]

I just noticed this exact same thing on the highway today, except neither of my axle seals have any seeping or leaking. A couple days ago I did just discover my front diff pinion seal is leaking, so now I’m hyper paranoid/sensitive to all sounds. To be honest, I think it’s just extra nvh from the front driveshaft, diff, and cv’s rotating. It’s a lot of extra heft moving around quickly up there compared to 2h.

Normal sound, you can hear it with windows up also…almost sounds like it’s coming from passenger floor board area. Normal noise with 4A. Weeping front axle doesn’t look bad, almost like residual from something. I’d wipe it and see what happens.

 

[BoostCreep]

@FordTechOne any input on this one?