Okay guys we just had 20.5 in off snow 2 of my friends have 2004 f150 4x4 like mine. Mines a screw fx4 my friend has s screw lariat 4x4 and my other buddy a screw xlt 4x4. Both my friends 4x4 quit working leaving them stranded. I checked their trucks out the 4x4hi light on cluster is on I can hear the solenoid behind the battery click on and off as they toggle between 2wd and 4hi. But nothing happens at the iwe? What's the issue here.

 

iwe 's are vacuum actuated iirc so a vacuum leak somewhere most likely

 

I thought if vacuum was lost dumped or not present the iwe lock in to 4x4?

 

Are you sure they're not locking? Jack them up and give them a spin in 4wd and see if the shaft moves. If it doesn't, I'm apt to think the iwe hubs are broken and crap got into them and made them stay open... though it's weird that it happened to both trucks, both tires. Beyond that, maybe transfer case issues...

 

And you are correct.

 

Did you already also try 4L?

 

Yes I hear the solenoid clicking but nothing at the hubs

 

Any other words? Trying to fix these things the obviously have a flaw if two did it in the same day in my area

 

Here's the problem. You're saying two trucks both had their two front wheels fail to move when engaging 4wd. Two trucks in the same day. Four wheels failing to move. To me that says either four IWE hubs failed to lock properly, or two transfer cases both failed to engage. It is more statistically likely that two pieces of equipment failed vice four, so you need more evidence. Why are you saying the 4wd didn't engage? Is it just because the front wheels didn't move? You need to jack the trucks up and put them in both 2wd and 4wd, under power and moved by your own hand, and view if the front axle is moving or not and if the truck can spin them on its own. Basically, run them through every possible scenario of operation and see which one doesn't do what you tell it to do.

Troubleshooting. It's all just troubleshooting. Narrow this down.

 

Trucks will go in 2wd. Click it in 4hi the 4x4 symbol is on the cluster I can hear the solenoid by the battery click. I haven't jacked either truck up we've had 20.5 inches of snow just to see the vac lined to the iwe Id have to spend hours chipping the ice off the a-arms and hubs lol. Both of my friends said their 4x4 worked the last snow storm two weeks ago the snow was 8in then. Think maybe their vac line got knocked off the iwe hub but I can't see anything under the snow ice ect. Mine works lol f-it lol