Hi all I'm new here and am looking for some help. I have a 04 F150 FX4 the front hubs were making a clicking noise so I had them replaced . $300 plus ouch! anyways on the way home the right side made the noise again. When the truck was in overdrive going up a slight grade I put it in 4wd and the sound went right away. BACK TO THE REPAIR SHOP !!!! SO after an hour of testing for vacuum leakes etc etc etc nothing found ??? what we did find is when the truck is in overdrive the vacuum pressure drops way down ????? any help would be greatly appreciated

 

i had the same problem with my 04 as well. It clicked for weeks and no one could find the problem.. checked the transfer case, vacum lines.. but we eventually found out it was the actual HUB its self.

Now i might have this backwords but im no mechanic but this is what we found. when the truck is in 2 wheel drive the truck is supposed to use vaccum to pull the 4 wheel drive out of place.. when your truck is in 4 wheel drive the hub is activated and is in contact. What my mechanic found that the hub was slightly touching in 2wd and causing it to grind off part of the hub creating that clicking sound.

Hope this helps!

 

Check your IWE solenoid.

 

I know this is an old post but I have the same issue as the original poster and was hoping it was resolved. When my truck kicks into overdrive it is pretty sputtery as if it is misfiring but never throws a CEL and then seconds later the hub starts to grind. I have replaced the iwe solenoid, all the vacuum lines and the iwe itself. Still the same problem. Is it perhaps misfiring and causing vacuum to drop somehow to the point where the iwe begins to engage?

 

Check the "Diagnosing Your ESOF" thread by VTX1800N. That is the ultimate thread on diagnosing your 4x4 system.