Originally Posted by Josiah

you went within five minutes of him saying this? Quick response lol. Unless your hubs are damaged you shouldnt' be getting clanking from the front end when there is no vacuum pressure (engaged). To test the solenoid there are 2 lines, disconnect them and feel for pressure on the tips of the rubber hose, with the key in the on position. Also listen for the solenoid to engage (pretty loud) when you turn the key on, have someone do this in the truck and go under your hood while he turns the key to on then off. There should be a very clear clicking when the solenoid engages...the solenoid is on the pass side firewall.