Hello all
Need some advice on solving an IWE issue on a 2016 f150 lariat 5.0 with 120K miles.
Swapped out drivers side IWE due to Grinding which did solve that issue.
Currently CVs won't disengage when driving in 2WD and I believe this issue may have pre-existed the swap.
here is what I've discovered so far.
1- Pulled off IWE vacuum line from drivers side wheel, attached gage and read vacuum WHILE driving. Was a constant 22 inches
2- Switch from 2WD to 4, vacuum went from 22 to 0 inches as is expected. Good solenoid?
3- Switching from 4WD to 2 while in park, it will not pull a vacuum until I put it in drive.
4- While driving and noting vacuum from drivers side wheel, passenger side CV continues to rotate while in 2WD.
5- When driver and passenger wheel is individually jacked up off the ground, the hubs will engage and disengage CV as you would expect, leading me to belive the IWE isnt misaligned.
6- I bypassed the solenoid and spliced the vacuum lines and had no positive effect while driving.
what do you all think, any advice is highly appreciated.

Thanks
ken

 

Not sure you have a problem, or I'm missing something.
You have a Lariat with the TOD transfer case. It's normal to have a slight amount of power to the front end due to the nature of that TC. In 2H, your IWE's won't be engaged, but the driveshaft, diff, and half shafts will be turning.
Is that what you're seeing? Or as said, did I miss something?

 

Johnday
when i jack either front tires off the Ground in 2H and rotate tire, CV do not spin. I engage 4A and they spin.
when im driving both CVs are spinning while in 2H.
are you saying the two front CV axle should always spin?

 

Yes, you have the Torque on Demand transfer case. For lack on my part of a better explanation, your transfercase "leaks" a slight amount of power to the front diff. The video attached is an explanation of the Raptor TC, but yours works close to the same, as the TC putting power forward, even in 2H.
Bear in mind, the half shafts won't turn at wheel speed as if you had the TC in 4H/4A, they'll turn much slower.

 

Johnday
Got it. Thanks for the reply and that explains everything im seeing. I was concerned that I installed the IWE incorrectly.
Come to find out the intermittent groaning/grinding noise from front left i was experiencing was not the IWE, but the needle bearings in the hub, as i noticed the cv shaft at that location has a gnarly groove cut into it. I packed the bearings and the noise MOSTLY disappeared, now just has a low level hum at 50ish MPH.
I originally thought IWE cuz it would primarily disappear when i engaged 4H, thought now is perhaps engaging the teeth takes pressure from the shaft off of the needle bearings, dont know for sure.
Just have to save up the pennies for a new hub and CV axle.

Thanks so much for your knowledgeable repsonses!!

 

You're very welcome, glad to help.
I've noticed over the years, that as soon as a person starts having funny noises and things coming from the front, someone will automatically say it's IWE's. The info you gave in your first post tipped me off to what was going on.
You did some good trouble shooting.