2006 F150 5.4L 4x4
The other day my truck was in 4High when I started it up and went to move it. I switched it to 2H and started out, but the O/D off light started flashing and the Trans Fault message came on in the display. After shifting through some gears and back and forth between 4H and 2H, I finally just shut the truck off and when I re-started it the warning light and message had cleared. Hoped it was just a glitch, BUT... today I had to drive my wife to the hospital and on the way I started hearing this nasty grinding sound from the front left wheel area. It was a bit of an emergency, so I couldn't stop. After getting her checked in, I went out and looked around under the front, saw nothing out of place and test drove it for a bit, switching into 4H for a while and then back. The noise persisted, but then it stopped and after driving around for a bit it stayed quiet, so I hoped that it would stay put. Driving back home it was good most of the way, but then it started up again.
It's really nasty sounding, like a ratcheting noise, and the steering gets tight, then it makes this whirring sound and with a clunk it stops and seems fine, but it just starts up again a few seconds later with the ratcheting. No warning lights or messages though.
I know it needs to be looked at, but does anyone have any idea what might be happening.
The timing for this couldn't be worse, I just found a buyer for the truck, which is in excellent shape otherwise.
Any help is greatly appreciated.

 

Hey,
Sounds like your having a problem with one (or both) of the IWE's. These are the vacuum units that engage the front axles to the hubs when you shift to 4wd. Quick check for this is to hook up a vacuum pump to the IWE, (which are located between the hubs and the axles) and see if they hold vacuum. If they do,you likely have a problem with the solenoid that controls the IWE's. If in doubt, take it to yor dealer or a shop familiar with this system. Good luck! BTW, IWE stands for Integrated Wheel End Cheers!

 

Thanks Pickled,
I'll look into it tomorrow, it's dark out now. I had it into a garage for a safety inspection for the sale and I'm wondering if they pulled a vac line off or fouled something up. However, I did also get that error message the other day and that was before the inspection.
Well, I hope it isn't an expensive repair, that's all. I don't want to sell the truck with the problem obviously, but I already have to redo the rear brakes including the rotors for about $600.

 

Another question.
Probably obvious, but I did drive it a bit with this happening. What possible damage could result from that, other than having to replace the IWE?
Thanks again.

 

It is possible that the spindle assy's may need replacment due to possible dog tooth wear. Not likely but possible. Good luck!

 

If you had a flashing OD light and a trans fault, you need to get the codes read. The freebie scanners at Autozone can't read trans codes, you need to take it to a shop that has a capable scanner.

 

Ok, I jacked the truck up, spun the tire around and wasn't able to hear any ratcheting/grinding noise. Took the wheel off to better access things, followed the vacuum line back to the solenoid behind the battery and couldn't see any break or disconnect. Took the vac lines off the IWE and got suction in 2H but nothing in 4H. Is that the way it's supposed to work? I thought it'd be the other way around.
Anyway, put it all back together, took it for a spin around the block and no noise for quite a while, tried it in 4H for a while, nothing, but then it started up a bit once (in 2H again) and then stopped pretty quickly.
Also, wasn't able to engage 4Low at all, but it's usually kinda tricky anyway.
Thanks for your input on this.

 

Yes, thats the way it works. if your noise is happening in 2wd, then its deffinetly a IWE issue. Check if the IWE's hold vacuum and do not leak down. (with vac pump) If theyre ok, smoke test vac lines to check for leaks. Since you have a CEL, recommend you have it scanned. Would'nt be surprised if you hade a bad 4WD solenoid. Cheers!

 

Yes. Vacuum disengages them, lack of vacuum engages them.

About those codes?

 

Okay, got it fixed. Sure enough it was the IWE. They swapped it out for a new one and $500+, I'm back on the road, good to go.
If I had a heated garage I probably would have attempted this myself, but it's been hovering around -15c or so for the last few days here. Also, needed to get it done for the sale.
Now another $600 for the rear brakes (yeah, I know I could do those myself also, but...). After that, my baby is sold. It was a great truck, served me well (up to this weekend), but I'm sure it'll serve the new owner well for several more years.
Yay Ford!
F150's rock!
Thanks for your help.