What is this seal?

[code.mafia]

We have two F250 4x4's (2005 and a 2006). I noticed this seal looking thing around the end of the front axle (one on each side) flopping loose. Maybe it's an axle seal? Anyway, both of them are loose and dangling on both trucks. It looks like it's stuck up in there right in the pic, but I can pull it back (outward) and it will just spin around whatever it is called (yoke?) that goes throught the center of it, like it has come apart from a portion of it that's inside the axle tube? Right now it kind of resembles a rear main seal.

You can see the black mark to the left side of it where its been flopping and rubbing on that yoke or whatever it is. The pic is of the front passenger side.

Is this common? Do I need to replace it quickly? If so, whats the best way? Is it a major headache to replace?

[sinner6.0L]

it's a axle dust seal. not really critical other than keeping dirt and rust away from the inner axle seals which seal the front diff fluid

It's extremely common to have this concern infact there is a new design seal that presses into the axle tube

To change it you need to remove the front hub and remove the axle. you'll need knuckle seals, hub o-rings and the new axle dust seals

here are the part numbers, you need 2 of each

knuckle seal 5C3Z-3254-AA
wheel bearing o-ring 5C3Z-4A322-AA
axle dust seal AC3Z-1S175-A

[code.mafia]

Yea that sounds like a PITA. If it's not hurting anything too bad I think I'll leave them alone for now. Can I just cut them off since they aren't doing anything?

[sinner6.0L]

hmmm, I wouldn't totally remove them, even being pulled out it may keep a stone or something larger from lodging in there

[code.mafia]

Gotcha. Thanks.