Hey guys, I know im new around here, and Ive searched the forums but cant find anything with the same symptoms as what Im experiencing.

Truck:
2006 F150 Supercrew XLT 4x4
170,000 miles
2 inch Skyjacker front leveling kit installed in 2008
33 - 12.50 - R17 Mastercraft Courser CT Tires on stock rims
I am the origional owner.

In 2wd the truck drives and turns as normal, no abnormal sounds / shaking noted. When I flip the electric switch to 4H and the truck is moving, a loud "grinding" sound begins and wont stop until the truck is placed back into 2wd. I say it is a grinding sound, but to me its better described as similar to sand in ball berings type of sound. The sound gets a higher pitch as you accelerate. Yes I know per Ford you are not supposed to operate in 4x4 above 40 mph, and I never have at any time.

If anyone has any ideas on what this could be, I would greatly appreciate the help! Thanks in advance!

 

May be an IWE problem.

https://www.f150online.com/forums/ar...then-some.html

 

Amen to that....I'd hazard a guess that the solenoid is not opening enough. All I can say is good luck

 

UPDATE!!!

Alright guys, I replaced the IWE solenoid that is behind the battery. Since replacing this, I no longer hear the grinding sound when I engage 4H or 4L or 2H! I could not tell if the 4H or 4L was actually pulling, so I chained the truck to a tree to see if the front wheels would spin. They did not spin when in 4H or 4L! CRAP! The 4H and 4L lights come on respectfully when engaged. So, any ideas what could be causing this?

Thanks for the help!

 

Jack the front tires up (you can do one at a time or both) and start your truck. In 2wd, if you rotate the tire while it's in the air, only the tire should rotate. The CV axle should NOT rotate. Turn the switch to 4wd and rotate the tire again. The tire and CV axle should rotate together. Do this to both front tires and see what you find.

 

Is the 4wd manual shift or electric (switch on the dash)? It's possible that your front end is engaging, but not the transfer case.

 

Check out this!

 

It is an electric shift 4x4 system. I lifted the front end up, and turned the tires in 2wd while truck was running. Front axle did not turn, but clicking noise was noted in front driver's side wheel. Tried the same thing while 4x4 was engaged and the front axle still did not turn.

 

Sounds like you have the dreaded, yet all too common, IWE ITUS. As indicated in the video.

 

UPDATE!

Aight, got the IWE Actuator in from Advance Auto. Decided I was going to blow out all of the vaccum lines, disconnect all of them including the vaccum box and blew them all out, a little water residue came out of one of them. Unbolted the box and found a ton of water in the vaccum box. Got all the water out as best as I could and plugged the line going to the box. Tested all functions of the vaccum system and found that I was getting positive suction to both drivers side and passenger side while in 2wd, and was getting none in 4x4. Which I understand is how the system is supposed to work. YAY! This means that my solenoid is working correctly. Then I checked to see if I could turn the front drive shaft when in 4x4 which I could not, but I could turn it when in 2wd. YAY! I believe this means that the motor on the transfer case is working correctly!

PROBLEM! I am trying to replace the IWE actuator in the driver's front. I cannot get the 12mm star bolts of of the half shaft, because I cannot prevent the shaft from spining. ANY IDEAS????

 

I just followed the video ... Plus drained out vacuum box of water, and replaced solenoid too. Be sure to do both IWE's. Be sure to use Ford parts not DORMAN!

 

Drivers side vacuum leak I cut it out and spliced it with an old vacuum line that had an ID identical to the OD of the damaged one. Smatterd it with some gasket material for good measure.