so my 05 5.4 4x4 has started doing this thing where there is a humming coming from the front end when I drive it gets louder the faster I go and changes tone when I turn any ideas btw I replaced my iwe's not long ago

 

Tire pressure?

 

right at 35 where they should be. it does sound like I have two big mud tires on the front

 

Symptoms sound like wheel bearing(s) to me. Especially If the tone changes when turning or shifting weight during a lane change, etc.

 

I was kinda thinking that if I replace them do I need to but the whole assembly for like 150$ each or can I just get the bearing and install them ?

 

so today I tore the wheel bearings apart and the passenger side defiantly looked like it had less grease but neither looked that bad I did not find any metal shavings and they seemed to spin alright so I repacked them with grease put it all back together and there is still a slight humming don't know how perfect these bearings need to be anyone know?

 

4x4 actuator.

 

I just read that you did them already. I'm thinking you have a vacuum leak somewhere. Could be a pinhole in the lines themselves.
I had this exact same problem a while back. Sounded like i had a mud tire on the drivers side. Dealer replaced a wheel bearing, wasn't it. Transfer case motor, wasn't it. Then they did the actuator on the passenger side and it went away.

 

Bearings on these seem to be very sensitive. We see them go without any symptoms on examination (no play, no visible damage, etc).

 

well I ordered two GMB assemblies off amazon for 180$ total are they any good?