hello all! Great and very helpful forum. let me say before i joined, i read alot on the "air blowing out defrost" posts and fixed mine in a couple hours today. cost 3 dollars too lol.
anyway, my problem is i just bought this 99 5.4 EB expedition. it has 176k on it and runs, shifts, does everything like new. i dont beat up my vehicles so i expect another 75k out of her. all hwy miles of course.

now the only problem i have is when i switch to 4wdLow i hear the "ka-chunk" and the light displays on the dash properly. i tested it in a field by my house and noticed only the back tires spin. even had someone watch.
skip forward, i jack all 4 wheels off the ground and engage 4wdlow. put it in drive and the front isnt spinning at all. i can move the front tires by had back and forth with no grinding sounds or and sounds what so ever. i also checked the half shafts up front and they are NOT turning. kind of rules out the hubs, correct? they do move with the wheel when i manually rotated it. thinking the transfer shift motor is SOUNDING like its working, but not really. am i troubleshooting this correctly? have never owned a 4wd truck of any kind.
thanks to all who read this.

 

Either fuse #104 is blown, or the front clutch in the transfer case needs to be replaced.

 

I think the '99 has the vacuum actuated front axle. Your actuator could be shot, solenoids on the passenger side firewall could be bad, or you could have a vacuum leak in the lines in between

I had the exact symptoms you described on my '98, turns out my actuator was bad on the axle. You can check it easily enough by removing the plastic cover on the front axle and watching the valve while someone shifts it into 4wd. it should move the lever to one side in 2wd, the other in 4wd. if it's not doing that, your front axle isn't engaged, even though the t-case is.

 

just checked fuse 104. its fine. ive heard about vaccuum actuators on these 4wds but thought they were in the wheel hubs somewhere. ill do what you say and check that out tomorrow. i dont need 4wd but like when all the bells and whistels work as they should.
alloro, basically, what would be involved in changing this transfer clutch?


edit: if the actuator was bad, would the lights for 4wd and 4wd low still come on? just curious.

 

Yes. I removed my actuator altogether, disconnected the solenoids and replaced it with a Posi-Lock cable. My dash lights work when i shift the OEM ****, but I'm not really in 4WD unless I engage the Posi-Lok

https://www.ford-trucks.com/forums/1...lok-cable.html

 

so theres 2 solenoids near the battery and one vaccuum actuator underneath near the half shafts? just trying to get it straight and btw, thanks alot. i hope its one of the three. if im hearing my transfer case motor moving into place, then i can prob rule that out right?

 

Yea. Behind the battery, on the corner of the firewall there should be 2 solenoids. If you follow the vac lines, you will come to a junction that's along the block, under the battery tray. make sure that's connected. continue to follow it to front axle, should disappear behind a plastic cover near center of front drive shaft. That cover is held on by 2 or 3 bolts. if you remove it you'll see the plastic actuator. If you start the truck and watch te actuator while someone flips the truck into 4wd you should see it move and stay until it's switched back to 2wd. if that isn't happening but you can hear your t-case shift ( and the dash light is working) your problem should be somewhere between solenoid and actuator. At least that was my experience.

 

You only have the vacuum actuator if you have a 2H position on your selector switch. I didn't think there was one in 99.

 

Removal and disassembly of the transfer case.

 

alloro, u r correct sir, i have "4awd, 4hi, 4lo" settings. im still going to have a quick look and see if theres any vaccuum lines or solenoids to check. and removing that transfer case probably wouldnt be the most difficult thing ive done. considering the stock ride hieght of these trucks theres plenty of room to move around under there. ahh well, ill update when i figure it all out. thanks

 

WHOOPS! Sorry about the wild goose chase, for some reason i thought i'd read that they used the vac actuator on '97-'99, but I have no doubt Alloro has forgotten more than I'll ever know about these gas guzzling beasts!! Good luck with fix

 

ok, so i got under there. now i might be new to 4wd but there is NO drive shaft going into the front case!!! its missing. what the hell? what would this part be called? where would i find one? im sure they did it cuz of a problem with the transfer case but i atleast want it hooked up so i can trouble shoot the problem.
i cant find out how to upload a photo but you could see, theres just a missing drive shaft!!
thanks so much guys

 

Tell me you didn't just say the drive shaft is missing and ask us what that part is call all in the same paragraph?

Your best bet at finding one is at a junkyard.

 

lol, a fit of stupidity on my part, just a lil amped about it being something so simple. now as long as my hubs lock, the clutch in the transfer case is good, im looking at a 90 dollar fix plus some good bolts. i thought it might have some more particular name but obviously no, its simply called a front drive shaft. will post more when i know why these guys originally pulled it, must have had a problem but we shall see

 

so i have another question: i had my friend pull forward slowly in the default 4awd setting and noticed the front half shafts turning. does that mean the front hubs are locked? they shouldnt be engaged unless im in 4hi or 4lo correct? keep in mind this is all being noticed WITHOUT a front drive shaft. i have a good feeling thats why the previous owner removed the shaft, it was stuck in 4wd all the time. what controls the wheel hubs? im assuming another vaccuum solenoid somewhere? ill know more when the drive shaft comes in and i get more data