Well, I've done about enough researching around forums to make my eyes bleed.

My issue goes as this:

2004 F150 Super Crew Lariet 4x4 with limited slip. Center console with electonic switch 2wd/4hi/4lo on dash right of steering wheel. Let me know if any other info could be helpful to my case.

My 4 wheel drive does not work.

When the truck is in 2wd I have no issues, no sounds(I've heard anyway) or anything. The only questionable is when turning with wheel at full lock in either direction at low speed, my front wheels grab/lunge. Not sure if that is normal or not on these trucks.

When I put it in 4wd in the snow, it acts as though it wants to engage, but the second any power is applied to the wheels, the back wheels just spin and it makes a higher pitched grinding/chattering noise up front. It will also lightly clunk into 4wd with little power applied to the wheels, but once it has accelerating power applied the front diff "pops" and is clearly no longer engaged.

When in reverse in 4wd, it makes no noise, but still doesn't work.

Yesterday I had it in the shop for an oil change and to rotate my tires. While it was all off the ground I turned the ignition on and put it in 4wd. Both back wheels turned it the same direction(limited slip) as they should, and the front left wheel turned fully engaged with them. The front right wheel did nothing and turned freely on its own(assuming because front it open diff?). One oddity noted, when the back wheel were rotated one full revolution, the front rotated 2 full revolutions(also assuming this is because of the front diff being open and rear being locked?).

When I spun both front wheels by hand regardless of 4wd turned on or not, IIRC, they both made a clicking/ratcheting sound as the spun.

I left it in 4wd when I brought it back down on it's wheels and backed it out of the shop into the unplowed area of snow, I lunged the throttle a touch and the front end dropped as the front wheels gripped and slightly broke loose in the sticky snow. It was fully engaged and working properly for a second. I then put it in drive and tried to move forward, soon as any power was applied it "popped" out of engagement in the from diff and was back to 2wd and light grinding noise.

Another note, our first big snow fall a few days back is when I first had a real issue with the 4wd not working at all. It had snowed pretty well and I didn't feel like shoveling the driveway because I was running short on time to make it to work and my wife had the day off work and didn't need to go anywhere. I started it, put it in 4wd, let it warm up a bit, proceeded with trying to leave. This is when it all began with the 4wd not working at all and grinding. As it made that noise, it sounded pretty light to me in the cab even with the window down. But, as my wife noticed me stuck in the driveway she stood in the front door watching with the glass storm door still closed. She said she thought that "light" grinding noise I heard, was actually quite loud from where she was standing, 60+ ft away.

Previous issues I've noticed with my 4wd that may help diagnose my exact issue, it has had a frequent issue the past year or so with, when engaaged, if I applied too much acceleration, from a stop or not, it would suddenly "pop" out of engagement as I've previously noted on, but I would immediately let off the throttle and it would reengage right away.

On two other occasions, it has refused to engage into 4wd no matter what. I simply contributed it to the extremely cold weather during the occurrence, as it worked just fine the next day and/or the next time I placed it in 4wd.

4hi/4lo light always lights up in the gauges as they should and as if everything is working normal.

Hope that was easy enough to follow. As I said, I've been staring at this computer screen for way to long now trying to get this licked.

So, IWE's? Actuators? Vacuum? Sell old, buy new? What do you guys with experience in the subject think??

 

I am sort of in the same boat, went in the snow today and no 4x4. It worked acouple of weeks ago when it was mild and raining, I can hear the tranfer case engage and the solenoid click but when I put power to it the front does nothing. I did have some grinding type of vibration about a month ago then it stopped and all seemed fine. I wonder if we have moisture in the system and it is froze up.

 

Took mine down to a buddy's shop and put it on a hoist, the vacume line was off of the IWE on the drivers side, put it back on and it worked fine. Check all your lines and make sure they are connected.

 

"When I spun both front wheels by hand regardless of 4wd turned on or not, IIRC, they both made a clicking/ratcheting sound as the spun."

In 4WD= This leads me to thinking the wheel hubs and/or IWE (some call these "actuators") gears are worn off. In 2WD= You may also have vacuum issues that led to this damage. Good news is there is plenty of help here for those items and the work is not too difficult to do.

From your excellent descriptions, it sounds as though the transfer case and shift motor are working fine.

Here are the "go to" threads for vacuum trouble shooting, and for IWE replacement.

https://www.ford-trucks.com/forums/836438-everything-you-wanted-to-know-about-the-iwe-system-and-then-some.html

http://www.f150online.com/forums/2004-2008-f-150/360269-iwes-removal-replacing.html

I would start with trouble shooting all the vacuum system (lines, check valves, solenoid) as that's the cheapest stuff, and if it's not right the mechanical parts will still get torn up again.

Online price for IWEs are about $80 each (hopefully all that needs replacing) and front hubs are about $200 each. Solenoid for the vacuum system is about $30, and is often the culprit that begins the road to destruction for the rest of the system. Doing the work yourself can save you hundreds of $$ in labor costs.

 

Here's another excellent thread...newer trouble shooting guide and explanation of the 4x4 system.

HOW TO: Diagnose your ESOF 2004+ 4x4 problem - Ford F150 Forum - Community of Ford Truck Fans

 

Thanks for the great info!

Where is the best place anyone has found these parts online? Through my research I've seen many people say they got/can get them for decent prices, but nobody states where they actually got them. I haven't gotten into resourcing the parts much yet, since I've yet to dig into the issue. My work and family schedule has been pretty busy lately.

 

The article 60DRB referenced was mine.

As for a source for the parts, Tasca Ford is a reliable and inexpensive source for the Motorcraft part if you can wait a few days for shipping:

2005 FORD F-150 Parts - TascaParts.com

It's a little cheaper to buy from them off their eBay page as they ship free: Brand New 4WD Auto Locking Hub Actuator 2004 2012 Ford F 150 with 4WD | eBay

You can also get the Dorman equivalent for a little cheaper off Amazon:

 

May also check with Silverstate.com out of NV.

 

I have yet to see prices at Tousley Ford be beat, compared to other Ford dealerships. Tousley Ford Parts Depot

Plus, Tousley is a supporting vendor here at FTE. Tasca and Silverstate aren't.

Stewart

 

I have similar issues with my 4wd. There's a switch that you turn and a light on the dash will come on telling you whether it's hi or low. But for whatever reason, when switching to 4wd, there's no light or any feeling that the front wheels were engaging. I am assuming it has to do with something electronic? Please help...

 

The most frequent cause of no dash light in 4x4 is water intrusion to the IWE solenoid on the firewall behind the battery. Check to see if yours has a plastic rain hood. They can be found cheap on eBay or Amazon.

 

Another common "no dash light" is a stuck/binding shift motor (on the transfer case). Try tapping on that while shifting to 4wd... they are often the culprit if not exercised regularly. Many owners of 4wd trucks don't use them as such it seems.