Ok read the posts about bad IWE solinoid causing metal scraping/grinding noise coming from front of truck. My noise just started yesterday, noise goes awy when I put truck into 4xhi. I bought new IWE Solinoid installed it started up truck for a test drive noise occurred almost instantly. Am i a dork did i need to let the pressure build up in the system before driving?? I also noticed that when I removed the old silinoid vacum lines I didnt hear anything. When I removed the lines from the new solinoid I heard air pressure being released from the lines.. Any help will be be appreciated I dont think I could have damaged the hubs/splines since I didnt drive at all (2-3miles max) with noise grinding.

 

check at each wheel and make sure the vacuum lines are plugged into the IWE itself, they can be snagged and pulled off easily.

 

Thanks checked the lines at the wheels for cracks and pulled them off to check for water. Mechanic friend told me to start the truck and let idle for a few minutes to allow pressure to build in the solinoid. Tried this and test drove truck, noise still happened, also put old solinoid back on truck and hooked up programmer to see if any trouble codes appeared they did not.. Now im more confused ...

 

You need to get a vaccumn gauge and check at the hoses off the hub and see if you are getting vaccumn you should have around 22 pounds of pressure at both sides. Thats the first place I would start. You could also have a bad check valve that comes off the solenoid. Check vaccumn at the hubs first.

 

I had the same problem.
It turned out to be a leaking iwe.
You can check it with a rubber hose and suck up vacuum and seal it with your tongue .
If it holds, all is good, if not repair it!

 

i had the same problem, turned out that BOTH hubs/IWE's were bad, the outer boots had torn and water go into them makeing them rust. Replaced both around $200 total and good as new. Not that hard to change.

 

mike, you said that you replaced both hubs for 200.. correct? did you do the work or did you have a dealer?

 

sounds to me like one or both of your 4wd actuators are bad.

 

Get this!

Just got my 07 back from the dealer today, I had the exact same problem you described, gringing noise under load only and it would go away when ever I turned on 4X4 manually. Basically the 4X4 was fully disengaging. And it happened last Friday.

I had the shop manager test driving it with me yesterday and we talked about the IWE Solenoid most likely being the culprit. They changed the Solenoid with the new harness (bigger cover eliminiating water infiltration), it didn't solve the problem so they also changed the actuator on the right hand side as well as the hub assembly. Was very happy when I found all this out.

Took the long way home after picking it up. Ran great the whole way except after I had to slam on the breaks and swerve to avoid ramming someone from behind. I gunned it on the green and low and behold I hear the same grinding at first on the left side this time and then it sounded like all over the place. Pulled overand vented on the phone with my wife, decided to turn back to the dealership but as I was drving back I couldn't duplicate the grinding no matter what I did.

So I'm really hoping it was the pressure and sytem sorting it outself out after the new parts installed and that the sever breaking and swerving caused it. Needless to say I'll be monitoring this, if all the actuators and hubs need to be replaced then so be it.

Hope this helps you a little. I'm lucky I have a year left of powertrain warranty.

Dre