I have an '04 F-150 xlt, 5.4ltr, automatic, 4x4. A couple of weeks ago my truck started making a crazy *** noise. While I'm driving it sounds like a gear is lose or something. It makes an annoying rattling noise like something is free spinning in the transmission or transfer case. It also sounds like it's barely making contact with something with teeth on it. It's like something isn't fully engaging, it does it the worse while I am on the throttle, once I start coasting is dies out slowly. I found out that is stops immediately when I put it in 4 wheel drive. What could it be?

 

IWE solenoid? Mostly because you said it stops when in 4wd. Check it out.

 

I done some research on this IWE solenoid, I had never heard of one. Every forum I found with this problem matched my problem to a T. Now, are they expensive, and are they a bitch to change? by the way, thanx man

 

They cost under $30 - you should be able to get one at your local ford dealership. Make sure its the new model with the protective case. It will take you about 10 minutes to replace. If you search on this forum, you will find step by step instructions with pictures, but basically its the small black plastic piece on the firewall behind the battery. There are two little hoses attached, that you have to pull off to do the replacement. It would be a good idea to disconnect them at the hubs too, and blow through the lines to clear them of any debris that might have gotten in there. They are the two little hoses (very much like the ones you disconnected at the solenoid) towards the top of the hub, and you can just pull them off. Good luck and let us know how it goes.

 

make sure the dealer gives you the new part and not the old one, it should have a cover around the solenoid.

 

A prank... Zip ties on the drive shaft LOL, J/K