2005 F150 SC 4x4, 5.4L, 111K miles

IWE (Integrated Wheel End ???) is the system that controls the engaging and disengaging of the front wheel locks for 4WD. Someone please correct if I'm wrong!

I bought this truck, from my brother, back in September (105k miles) knowing it needed some TLC. The first thing I did was change ALL fluids and filters. The transfer case fluid was quite dirty (clue). That surprised me since I know it wasn't used much. I changed it again Saturday (6k miles on it) just to get all residual crap out. It showed signs of heavy use (clue). I used it about 1 mile of the 6k.

I have been fighting MPG with this truck since I got it. I've tried everything I know and still a few MPG's short of where I think it should be (clue). Always thought it was the VVT going bad.

I"ve noticed, sometimes when I turn tight corners, something seems weird but couldn't figure it out (clue).

My 4WD HIGH light tries to come on but won't stay on (clue).

Early yesterday morning I read the IWE post by "xjcamaro89" titled "Everything you wanted to know about the IWE system…and then some". Excellent post followed by 22 pages of questions and more tips and suggestions from readers.
It's located in the "2004-2008 F150" section in the stickys at the top of the first page. Yes! I could have linked it but now people know how to get there.

I completed all the vacuum tests and the results are: 1 bad hub actuator, 1 bad solenoid, 2 bad check valves. This means my front axle and transfer case have been spinning all the time that I drive. Transfer is not locked in but spinning freely at high speeds for long periods. I believe the front driveshaft turns a sprocket with a heavy duty chain to another free spinning sprocket until the transfer is electrically locked in. Any way you look at it, that's a lot of gas pissed away, a lot of ware & tare on my transfer and front differential. I used my vacuum pump to manually disengage the hub and it was amazing how easy the wheel would spin, opposed to when the hub is locked because of inadequate vacuum to hold it unlocked.

I believe everyone with an IWE system on their truck should run these test or have it done. MPG alone, I know I've waisted $500 since I bought it.

I'm waiting for parts and will post results of MPG improvements (I hope)! Also I wonder how many people are driving around like this. How many people are blaming worn out VVT for bad gas mileage. How many toasted transfer cases this system has caused.

Hope this helps others! Thanks to xjcamaro89 and others I've learned from!!

 

Is it possible to eliminate this system by using manual locking hubs and plugging the main vacuum line at the source??

Any other tips and tricks to this IWE system. I guess in theory this works in emergencies. If your stuck and the vacuum line is broken the 4WD should still work when you turn the selector or shift to 4WD. RIGHT???

I had an 85 Dodge that was the opposite no vacuum no 4WD and no fun for me having to tromp around in 16" of mud to reconnect vac line to reservoir before I could drive out!

 

keep thinking of more stuff to add.

This may be in other posts. Thought I'd add it here! A simple check to see if IWE is not working properly is to have someone watch the front axle from a a safe location. Have the engine running and the selector in 2WD. Then drive a few feet. If the front driveshaft rotates while the wheels rotate then something is not working correctly. While in 2WD the wheels should rotate free of the front axle. The hubs should be unlocked from the axle and spinning freely. As I understand it, having the front wheels off the ground and spinning them by hand will also work if the engine is running. Same applies, if front driveshaft rotates there is a problem somewhere in the IWE system. If the engine is not running then the hubs lock up because there is no vacuum and the driveshaft would rotate. Please correct me if I'm wrong.

 

Yup....so far your on the mark. I'm currently going through the same thing on my 06 F150 XL 4x4 with the 5.4 engine. My 1st clue was the sound of what seemed like someone beating on a tambourine in the vicinity of the front drive line but only when I accelerated (when engine vac drops). I drove it like that for about 2yrs also knowing that my front hubs were not locking as well. About a month ago I was servicing the truck and noticed that my drivers side wheel bearing was bad. I installed a new spindle and, while I was at it, I opted to also replace the actuating hub. Tah Duh!!! No more tambourine and my hubs locked...well....for a short while. I now have the same sound and non locking hub issue on the passenger side now. Go figure huh?
I did do some preliminary checking prior to changing out the spindle and actuator. My vac lines are good as well as my solenoid however, I do suspect that my vacuum reservoir tank may have a leak since the trucks tambourine sound only occurred during acceleration above 15-20 mph. I suspect that once the initial vacuum drops during acceleration from a standing start the tank doesn't have enough reserve vacuum to keep the actuators "sucked" back and they start to engage thus producing the sound of what to me sounds like a midget under my front end beating a on a tambourine. May I suggest also checking your vent lines that come from your actuators. If plugged you'll also have locking issues.
I understand from other sources that there might be an alternative that would allow for a swap out to a manual locking hub. I'm still investigating that rumor.
Thanks for your post. It's some comfort to know that we're not alone with these issues.
Capt'n

 

Also could be your check valves. Also found some on web under "vacuum checking switches"

 

After much more reading I see there are no manual locking hubs. What about electric vacuum pumps mounted closer to each wheel with one check valve each side. Activate by toggle switch or reroute electric from IWE solenoid. Flip the switch and instant vacuum, hubs unlocked. Eliminates the 20+ feet of vacuum lines and vents and 15+ connectors and at least 1 check valve.

Many people have issues with this system. In my case half the system went bad in 7 years.

 

I had to replace both IWE (one leaking and one had a broken internal spring) and the solenoid at just 44K, right after I bought my '06. It's still working fine 4 years later now at 97K , and I use the 4x4 several times a month. Still has all the original hoses and check valves.

 

Well boyz....I finally got around to changes the passenger side front wheel hub and actuator. As long as I had my truck up on my lift and threw on a new set of tires to deal with any future situations where that white stuff falls from the sky and makes our local roads seem like a skating rink. I now have full 4X4 engagement and now, when I shift into 2wd....no more jing-a-ling. Both the hub and actuator gears where beveled back about a 1/4 inch just like the drivers side that I replaced about a month ago. I now have a happy F-150 4x4. Yay!!
Capt'n

 

UPDATE FOR THOSE THAT WANT TO KNOW!!


Everything was replaced/repaired before Christmas and the IWE system is working great! Just in time for all the snow we've been getting.

I needed 3 check valves and ford would only sell system sections that included vacuum lines and other parts. I don't remember the price but it was $$$.

I measured each check valve opening and started searching. These measurements are approximate but served the purpose for finding replacements. The first 2 are ford part numbers: 1/8 x 1/8 is "DY-260", 1/4 x 3/16 is "YG-360" and the 1/4 x 1/4 is "14047619" (AC Delco part, couldn't find ford).

Hope this helps others!

 

Thanks for the info Bob. Mine are still in good shape but I'm sure others will find your part number invaluable.
BTW, gave you a Rep. for a job well done
Capt'n

 

I'm having a problem with my 4x4 not engaging. All the lights light up and I can hear a sound that kinda sounds like something is engaging but no 4x4. Neither tire spins btw. I thought it might be the hubs so I took them apart and saw nothing wrong. I put everything back together and bam it worked. Disengaged it and tried to re engage it and it wouldn't work. I got in a bit of bind the other day and I decided to see if the 4x4 would work and it pulled for about a second and quit. What could be my problem? And I did change my vacuum solenoid to the newer version with the water shield and that didn't fix my problem.

 

Good news, OP and CPT P.

A step/search saver for others reading here;

https://www.ford-trucks.com/forums/8...then-some.html

https://www.ford-trucks.com/forums/1...l#post12662529

http://www.f150forum.com/f72/how-dia...m-esof-186872/

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

 

Thanks for the pat on the back Capt'n Phillips!

Infantryman 1991, follow the test procedures and I'm confident you can eliminate items one at a time. Took me a good 4 hours to do the testing to determine what I needed to replace. I would suggest you test each part in the system as I had multiple failures. If I would have stopped at the first failure I would have had to disassemble the system 2 or 3 times instead of once and repairing it. Good Luck!

60 DRB, Thanks for the links! Now members can go to one post get most if not all answers.