Question for you all

[Tomringler]

What is the iwe solenoid and what does it do

 

[ExpeditionAndy]

What is the iwe solenoid and what does it do

The IWE solenoid engages the hubs when you put it in 4WD or AWD.

On the expedition the only the wheels rotate when you are in 2WD the axles and transfer case do not turn. When you engage the AWD or 4WD the solenoid allows the hubs to engage and drive the wheels.

I know that is not a technically accurate explanation but it should explain it.

 

[mindgame]

On the expedition the only the wheels rotate when you are in 2WD the axles and transfer case do not turn.

Actually.. This is slightly true..
The front driveshaft and TC are engaged and spinning in all modes while driving.

By having the TC/DS spinning, this will allow you to switch from 2WD to 4AWD to 4H while driving at speeds like 60+mph. If this was not spinning, just imagine the torque going to the TC from dead stop while the car is running at high speeds. I'm pretty sure the TC will be trashed.

While in 2WD and the TC/DS are spinning matching the spin of the wheels, engaging and disengaging the hubs are obtainable via vacuum. At matched speeds the hub actuator and CV spline will not bind thus allowing simple hub engagement/disengagement via simple vacuum is a snap.

 

[ExpeditionAndy]

Actually.. This is slightly true..
The front driveshaft and TC are engaged and spinning in all modes while driving.

I thought the 2nd gen Expeditions have this: Ford F150 - 4 Wheel Drive Disconnect - YouTube

The guy clearly states that the half shafts don't turn until engaged.

 

[eddiebauer04]

When is the last time you changed the rear diff fluid. I had a problem with my 2004 doing about what your talking about especially when accelerating. I changed the fluid and added two bottles of the friction modifier and I was good.

 

[mindgame]

I thought the 2nd gen Expeditions have this: Ford F150 - 4 Wheel Drive Disconnect - YouTube

The guy clearly states that the half shafts don't turn until engaged.

Some times the easiest way to see things is to just jack the truck on four jack stands and let the wheels spin and test each mode 2WD/AWD/4H..

You will see that the front shaft/TC is spinning regardless of which mode you set. The hub actuators will be disengaged only if there is a vacuum present. No vacuum, hub are engaged by default.

 

[sgtowing]

Does yours have the LSD? Mine is 4x4 buy when I bought it, when I would go around a turn, it would feel like it was binding up. I took it to the dealer and they said it was the LS in the rear end. The clutch was binding up. They replaced the fluid in the rear and that fixed the problem. there is some special kind of additive in the fluid that the clutch pack need or it starts acting up.

 

[soundtransmissi]

I talked with a mechanic whom I've dealt with before and he said that he one time worked on an Expedition that actually had dry rot on the vacuum lines which led to the grinding/clunking that I'm experiencing. he thinks that's probably it and not necessarily (just) the solenoid. Does that sound plausible? I'm going to take it to him next weekend so I'll report back what they actually find.

 

[Tomringler]

Don't know when any fluid changes where done just got it 1-20-2014, don't know if it has LSD or not

It is at the shop when they call me and let me know I will let y'all know

 

[jdecker]

Your mechanic is correct, it could be a vacuum leak. Check all the lines also the IWE itself could be leaking and there is also a vacuum reservoir that can leak. It can also be a bad vacuum check valve.

btw- if your front drive shaft is spinning while in 2wd mode your transfer case isn't unlocking as it should