I have a 2005 expedition, and having Vacuum line problems, they broke and fell apart at the windshield wiper pump. Am I correct this is why my fan won't blow in the passenger compartment? Why it won't go into 4wd? the windshield wiper lines are broke too. Now that the vaccum hoses and connectors have come in, time to try and get everything sorted out.. But is the 4wd like my old dodge ram where they used vacuum lines instead of electrical or mechanical to tell front axle to engage (love that the ancient jeep has manual hubs).