By: TN-F150

Tools Used: (once you remove the wheel…)

  • 13mm socket for outer axle nut
  • 21mm wrench and socket for tie-rod and ball joint
  • 24oz hammer to separate the above
  • (I also used a 10mm and 3/8″ wrench on the above end of threads hex to hold them from spinning)
  • 5/16″ wrench or socket for the IWE bolts

We all know how to remove the wheels and the rest is just a matter of removing the outer CV center nut, tie-rod nut and the upper ball-joint nut and separating both. After this there is (3) small bolts holding the actuator on the hub that get removed. Then we see inside the actuator and what I was not finding here or on the net to get my head around how this system worked. I kind of had an idea but seeing is priceless.

So once the shaft is out of the hub, the actuator comes right off it. The CV has a gear the contacts the actuator all the time and when switched to 4WD it is released into the hub where it grabs the hub gear.

You can see after I cleaned all the old grease and particles of actuator gear off that the hub gear DOES take some damage from this issue. The actuator gear is made much softer so it takes the majority of damage. I’m assuming the gear was already slightly beveled so the actuator gear can click right on but it did have some burrs along the gear teeth.

Next we see the difference new to old and what happens to it when you hear the noise. The new gear has a flat edge to the hub side of the gear and you can clearly see that on the old one this has been ground to about a 30 degree angle shorting the gear to the point of nothing more to engage, so with the open diff taking the path of least resistance that half shaft will spin when in 4WD and the other, even though it works, will not do anything. No 4WD…

Bottom line, if you hear the noise immediately try to switch to 4HI and try to make it engage, get it in to be fixed before the actuator or hub gear are damaged or do like I did and take 2-hours and about $130 ($43 for vacuum sol. (the cause of the malfunction) and $83 for act. (the victim) ) worth of parts and fix it yourself. That time includes rotating my tires, testing the 4WD system to see which actuator was bad and changing it. I could do one now by itself in probably less than 45 minutes.

Links:

Ford IWE Replacement Instructions

Everything You Wanted To Know About The IWE System

Intermittent Grinding From IWE

2004-2006 Ford F-150 Intermittent IWE Noise TSB 06-8-15