Front Hub Sqeeling

[Skorchrock]

My 08 has an esof system but when I manually lock the hubs I start to get this squeaking sound. In 4wheel high around 40+ mph it's a combination of light grinding/humming sound and squealing. After unlocking them and bing in 2wd, it will keep squealing for a short time. When the hubs are in auto and 4wheel high is on there is only a light squealing noise. Dose this just sound like the hubs need to be cleaned and re greased? Or is it more?

[Miller]

I'd pull that hub asap and see how dry it is.