Reddragon1260

Ok here is what happened. One day i get a call from my brother in law that he had totaled his car on the side of the freeway so i go over with a trailer to pick him up. I find out he ran off into the construction side of the freeway that was full of loose dirt and large clumps so i decide to throw my 250LD into 4x4 to get him out. Everything goes fine, but the next day i decide to try out the 4x4 again out at the ranch and nothing happens. No 4x4 what so ever.

When i first turn the key i see the "4x4" and "4x4 low" lights come on then turn off like normal but when i move the switch from 2H to 4H there is nothing even from 2H to 4Low. No clunk or click of a relay. Everything was working fine the day before but now i have nothing. There are no codes and no lights on i have just lost 4x4 entirely. i missed most of deer season because i can not get out to the feeders or blinds. I did remove the motor and checked the transfer case and everything seems normal just no sounds what so ever.

twoskinsoneman

TC motor is probably bad. Did you check to see if it's getting voltage?

F150lariatss

I've got the same problem, but have not had time to troubleshoot it. Here is a document that I found somewhere.

How to Troubleshoot and Fix F150 4X4 1997-2003
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I am posting this because it took me AGES to find this information and peice it together from many sources all over the internet. From a girl who knew NOTHING about these systems a few weeks ago - here is a quick and easy guide to troubleshooting your 4X4 problems -- mostly for Manual shift on the floor (MSOF) systems or what goes on mechanically after you press the button on the electronic systems. All you need for these tests is a friend, and a socket set.

The 4X4 works with two systems - the shifter on the floor manually engages the transfer case. It also causes a relay to ground one of two solenoids that cause vacuum lines to activate an actuator which engages the front differential. If either of these do not work, your 4X4 won't work.

In my case, ad most that I have read, the 4X4 simply does not engage and the dash light either always goes on or does not go on.

1. Rule out transfer case problems: This is easy - get someone to put your truck in 4X4 and roll forward while you peek underneath from the side. If the front drive shaft is turning, your transfer case is fine and engaged.

2. Check the fuse! #23 by the hood lever and parking brake under the front dash.

3. Check the functioning of the solenoids: this is easy as well. The solenoids are located in the passenger side of the engine compartment directly behind the battery on the firewall.

From what I have read, a good indication of a problem here is the absence of the dash light. You can get fancy and test them electrically (they should each have 12V power all of the time) but the easiest way is to put your fingers on the plastic caps and feel and listen for a click as someone shifts your truck in and out of 4X4. If they click - they are working! If not, this is likely your problem. It is a common problem apparently for these years of trucks to get water in the solenoids which then freezes and cracks them.
Here is some good info and part numbers if this is your problem
"The right solenoid (E8AE-9H465-AA) controls the vacuum to the return side of axle engagement diaphragm. The left solenoid (E8AE-9H465-BA) controls the vacuum to the activation side of the axle engagement diaphragm. Ford has been having chronic problems with water entry into these solenoids, corroding them from the inside and seizing them, as you've seen!<o ></o >
They've been redesigned and those old part numbers (E8AE-9H465-AA/BA) have been superseded.

The latest designs are listed as:
Disengage solenoid 6L3Z-9H465-A (identified by electrical connector rib at 9:00 position)
Engage solenoid 6L3Z-9H465-B (connector rib at 6:00 position).


3. Check your vacuum lines: This is a little tricky to do because they wind their way from the solenoids all the way to the 4WD actuator on the front axle. One hose leaves from each solenoid at the front (close side to the battery) and one is pink and the other is blue(greenish if older). Follow the lines down as best as you can, checking for spots with wear or rubbing. Also make note if they seem old and brittle as there could be a crack you don't see. Mine were rubbing a bit on the passenger’s side wheel well so check there. Now crawl under the truck and in the center on the axle is the actuator diaphragm. It is under a cover that is easily removed with a socket and the two hoses are attached to it. Pull the hoses off and while the truck is on, and someone shifts it in and out, put a finger over the end of each hose. The vacuum should alternate hoses when shifted and the pressure should be equal although it is surprisingly not a strong pull. If your hoses look good and suck like I said, they should be all good (this also confirms that your solenoids and vacuum reservoir are working as well.)

4. Vacuum actuator function: This is easy to check. Crawl under your truck, take off the cover for the actuator and watch as your friend shifts from 4X4 and back. When the truck is shifted to 4X4, the shaft should slide into the diaphragm, moving the lever it is connected to to the passenger side direction. When shifted back to 2 wheel, the shaft should slide out of the diaphragm towards the driver’s side. The movement is about 2 inches total and happens smoothly.


If this works, then you may want to check to see if the shift fork (the lever that the actuator moves) is not bent or broken, or the pin that holds it in place is not sheared. It this all good, then maybe your front differential needs help?

If the diaphragm moves stiff and short, it is one of two problems: there is a tear in the diaphragm or the shaft has corroded and is stiff and needs lube. To check if the diaphragm is just stiff, assist the truck by pushing the shaft in an out by hand. This should engage and disengage the 4X4. When I did this, I engaged the 4X by pushing the shaft in but it was very stiff and hand to pull it out again with leverage from a screwdriver. Mine was just stiff and needed lubrication - which worked! If you can move it freely by hand, I would say there is a tear in the diaphragm and you probably need a new one. Try ebay -- they are $100 where at Ford they are $460!! Part number is F65Z-3G360-BA

Hopefully this helps you out.

Reddragon1260

That guide helps but my problem is i get nothing from my 4x4. When i move the switch i get no clicks on the solenoids, no light on the dash, and no clunk in the T-case.

I dont know which wires to probe to see if i am getting voltage but i just hope that i do not have to take it to the dealer to get this thing fixed.

twoskinsoneman

Orange and yellow are the motor wires. See if your getting power. I understand you say you don't hear the relays...TBH I can't hear my relays and it's working fine. So just in case they are working but you can't hear them see if your motor is getting voltage.

twoskinsoneman

Of course I am assuming you've checked the fuses. This should be the obvious first thing to do.

charliedyal

Check the fuses & solenoids for power. Could also be a bad GEM.

Reddragon1260

i have checked all fuses that involve the 4x4 system and they all check out, still need to check for power to the motor and solenoids. But my worst fear is the GEM because this is a 1997 F250 Light Duty, i do not know if i will be able to find a NOS or good used unit.

hendricksn

Quick question my actuator doesn't fully engage on its own but it I help it with a pry bar it went all the way in. I disengaged it and re engaged it and it seemed as if it was working. Should I replace the actuator? Or hose it down with pb blaster and hope for the best