When not in 4 wheel drive should the front half shafts be turning? I heard somewhere they don't turn unless the truck is locked in but mine always spin.

 

So out of all you 4x4 guys no one knows?

 

They will always spin because they go threw the hub and the wheel is bolted to the hub so when the wheel rolls the axle with turn....

 

on the newer model fi150 when the engine is running vacuum is supplied to the iwes to disconnect them they should not be spinning try this raise the front of the truck so the front tires are of the ground engine off spin the front tires do the halfshaft move they are supposed to now start truck let run for a minute in 2wd spin the tires they should not spin try this and let me know the results

 

I am pretty sure the turn. Hard to confirm as I cannot hang under the truck and drive it at the same time. The IWE is what locks then in place. If you think about it they should spin in 2wd, that is how shift on the fly works right, lock in the IWEs and go.

 

on the newer body style they dont in 2wd vacuum is applied and keep the iwe seperate from the hub teeth when vacuum is not applied 4wd a spring forces the two together locking them in

 

Integrated Wheel End (IWE) System

The integrated wheel end (IWE) system contains the following:

Vacuum reservoir
IWE solenoid
IWEs (spring loaded vacuum hubs)
Vacuum hoses
Check valve
The IWE system uses vacuum hubs that engage the front wheel hubs to the front halfshafts or disengage the front wheel hubs from the front halfshafts.

The IWE solenoid receives engine vacuum from the vacuum reservoir.

When the 4-wheel drive system is in 2WD mode, the 4x4 module (PCM) supplies a ground path to the IWE solenoid to apply vacuum to the integrated wheel ends (disengaging the front hubs from the front halfshafts). In 4WD mode, the 4x4 module (PCM) does not supply the ground path to the IWE solenoid, vacuum is not applied to the integrated wheel ends and an internal spring keeps the front hubs engaged to the front halfshafts.

THIS IS STRAIGHT FROM FORD WORKSHOP MANUAL TO CLEAR ANY CONFUSSION

 

Yep they are spinning when the truck is in 2 wheel. What would cause this? Obviously i'm not getting my vaccum pressure. I'll check the vac pressure and make sure it's getting good suck lol. Wasn't there a recall on this?

 

there was a tsb for the vacuum vent solenoid on the vent solenoid the top hose is the supply vacuum and lower is sent to iwes check both top for vauum and lower to see if it holds vacuum if it dont hold vacuum block each one and try again i believe the larger of the two hoses at the iwe is the supply vacuum

 

Right on thanks, I'll give it a try!