Are the front hubs always "engaged"?

[Willonious]

Are the front axle hubs permanently engaged or is there a vacuum system or something to engage them like on an F250?

 

[Jeremy-WI]

My 2006 is always engaged, I can jack the front wheel off the ground and the front driveshaft turns when I spin the tire

 

[KJowner]

There permanently engaged but only driven if the transfer box is in 4wd

 

[duderz7]

Always engaged, the disconnect is at the transfer case