Tattrieman

Hey guys, new to the forum, have had a few ford trucks but never had this problem. I have a 2007 f150 fx4 offroad, 5.4. When i put it in 4hi the light comes on, truck makes a small jump/click and does not go into 4x4, tried this while stopped and while moving. Will also not go in 4lo. Any suggestions? Thanks

WXman

Sounds like the electric motor on the t-case may be frozen up. That's pretty common, especially if they aren't used often. Try smacking it with a hammer and see if it'll go ahead and make the shift. Sometimes that'll get them unstuck, sometimes it doesn't.

Tattrieman

Will give that a try this afternoon. Thanks!

WXman

If it's not the electronic shift motor on the transfer case, then it's likely a problem with your vacuum hubs. The lines could be leaking vacuum from cracks or splits, or you could have a faulty solenoid on the firewall where the lines connect, or possibly a failed hub(s).

Tattrieman

Whats the best way to about checking the vacuum?

techrep

iTrader: (1)

Vacuum pump.. you can barrow one from autozone. to troubleshoot.. dis connect the vacuum line from IWE's.. this should engage your hubs.. default mode is engaged..Vacuum holds them dis-engaged.. but, sounds like a T-case shift motor like mentioned above.

Tattrieman

I did try hitting the shift motor, didnt seem to work, but it has been very cold here lately, supposed to warm up through the day today and gonna give it another try.

Tattrieman

Tried again today, the shift motor is working, and clicking. When put in 4l the truck jumps a little but will not engage in 4h or 4l. Took a look at the vacuum lines and they dont seem to be cracked. Ordered a new vacuum solenoid, hopefully that will be the fix. Any other suggestions if that doesnt fix it?

jp360cj

How did you determine the shift motor was working? And have you pulled the vacuum lines off the hubs to see if they lock?

Shifting into low range and shifting into 4x4 are 2 separate actions. Low range engages the planetary gears; while engaging 4x4 requires engaging the front output. Without understanding exactly how the electric shift functions, I can't say for sure, but it is physically possible (in most t-cases) to engage low range without engaging the front output. So your t-case shifting into low range may not indicate that the shift motor/t-case is functioning properly.

Before installing the vacuum solenoid, try to diagnose the issue.

Tattrieman

I didnt pull the lines off. Do i pull them off the solenoid or down on the bottom end? Will try that this morning. And the current one just seems to be rough, they arent very expensive, wouldnt hurt to have a new one any. Truck wasnt maintained well by previous owner, have put tons of new parts on it, just 1 more to add to the list!