Another IWE thread

[dsiggi]

I hesitate to call it grinding. More like growling from about 7mph to zero.

I had this exact same thing twice, Dealer replaced IWE each time. I didn't self diagnose before, interested in your findings. My guess is some type of small leak that when the car comes to a stop the leak is too much to hold the IWE, but I could be wrong.

 

[rschap1]

I could only hear the "echo" of mine when driving when it was bad.
The sound had to bounce back off a guardrail, building, or something solid as I drove by.
Otherwise it was hard to notice or hear while driving.
Tires and road noise were enough to cover it.

 

[NorCal Offroad]

Holding vacuum now for the last ten miles. I’m thinking if it was a line it would not hold. Manual vacuum on the iwe works perfect. I’m stumped. Thinking about just doing the lines and actuators, to have a whole new system. I’ve already done the check valve and the solenoid. I’ve lost about 1mpg in the last few months.

 

[letsgetthisdone]

Delete the IWE's and move on with your life. I didn't even notice a fuel mileage change in my truck.

 

[dsiggi]

View attachment 446927

Holding vacuum now for the last ten miles. I’m thinking if it was a line it would not hold. Manual vacuum on the iwe works perfect. I’m stumped. Thinking about just doing the lines and actuators, to have a whole new system. I’ve already done the check valve and the solenoid. I’ve lost about 1mpg in the last few months.

what happens as you come to a stop to the vaccum?

 

[TomDirt]

It shouldn't change, as long as there's still vacuum in the reservoir and no leaks there. At idle, the engine is making lots of it.

 

[fordfreek]

If the system maintains vacuum at all times driving, try jacking up the front tires and see if the wheels turn independently of the axle while the truck is still idling and vacuum is still being applied post solenoid.
My experiences with iwe's is they start to engage while driving due to lack of vacuum, like under acceleration or long uphill stretches. If dirt has entered the system it will cause the check valve to fail almost immediately. That was my case. Warranty replaced both iwe's and all the lines with a new check valve.
Maybe things are still turning because of the transfer case, not the iwe's, if you're not losing vacuum.
I reached the point where I kept a gage teed into the post side of the solenoid all the time just for peace of mind.

 

[CleverGirl_]

View attachment 446927

Holding vacuum now for the last ten miles. I’m thinking if it was a line it would not hold. Manual vacuum on the iwe works perfect. I’m stumped. Thinking about just doing the lines and actuators, to have a whole new system. I’ve already done the check valve and the solenoid. I’ve lost about 1mpg in the last few months.

Is that a tire pressure gauge readout? I always wondered if those worked.

 

[rschap1]

I had done the vacuum gage on dash just like that when wondering what was actually wrong for me.
After replacing them, I have to tell you...it isn't nearly as bad of a job as I thought it would be.
I am used to never being able to disconnect/reconnect a ball joint.
Knocking the top loose, swinging the spindle around, removing and replacing the IWE went FAR quicker than I had anticipated (dreaded and feared).
When I did the other side for good measure, even faster and easier than first.
If no other cause found, replace or delete them.

 

[ALRaptor]

This may sound like a dumb suggestion, but are you running K02s? If so, how worn are they? I have about 30K miles on mine and I get a vibration from about 10MPH-0MPH. It can be felt through the whole truck. Wondering if this might be the issue here since you have exhausted everything else.