F150 4WD grinding noise

ford
f150

#1

I have an intermitent grinding noise coming from the front end of the truck. If I slow to 10 mph is may to away; if I turn on the 4wd I hear a ‘thunk’ and feel a mild bump and the noise goes away.



I searched the web and found a similar problem resolved by changing the IWE Selenoid - theory being issues with the vacuum. This minimized but did not solve the problem. My dealer has not been able to solve the problem … any ideas?