Hi everyone!

I have the classic grinding noise coming from my IWE on the drivers side.

My truck has been in and out of the shop and they cannot figure out whats wrong. They've changed the Actuator and smoke tested the lines, nothing come of it. I still have the grinding noise.

To double check, I purchased a vacuum pump, tested the lines, changed the check valve and there is no issue.

The only issue I can find is there is weak vacuum coming from the solenoid while in 2wd. (Yes i put a new solenoid in)

The vacuum coming off of the solenoid is strong then drops and goes up and down. What would cause this? vauum booster? Is there a pump? Any help would be a great help. Thanks.

 

What year and model truck you working on and which engine do you have?
I would think that there is a check valve somewhere on that system to investigate.

 

Its a 2016 f150 5L

 

Pull the vacuum line off the solonid output to the IWEs and let them lock the hubs in and drive it that way while you troubleshoot the problem or you will do more harm than good by letting it grind.