4x4 Makes Grinding Noise While Engaged
 

First off it's a 2005 STX 4.6L. This past summer I replaced the IWE solenoid & had both acutators replaced. Tried the 4x4 & it worked fine, but I did not go over 25 mph. Got a little snow this weekend and went to use the 4x4. Got up to around 30 mph and started to hear a grinding like noise from the front, in the middle, took it our of 4 and it went away. Both actuators and the IWE solenoid are new. The 4x4 does engage. Tried the search option, but couldn't find this. Anyone have any idea what it might be?

Thanks.

Its the vacuum lines that control the hubs. There is a 99% probability that your solenoid just behind the battery on the passengers side has gone bad/got water damage. The dealer has a new one that has a shield over it, that will fix it.

You will be damn lucky if the hubs are still usable, they might have chewed themselves down to little nubs that still wont work even with a new solenoid.

like the guy above said. probably the solenoid, that is if you didn't replace it with the newer version when you did it last year.
here's a link with an install and what it should look like
https://www.f150forum.com/f4/my-satu...ge-04-a-18608/