Hello this is my first post.
I have a 1998 4.6L f-150 supercab that my dad sold me...he purchased it with 12000 miles and it has served us faithfully for years and now it has 135000 miles on it . I recently got the engine tuned up (the last guy who did it did not put the grease stuff on the wires and it missed alot) I had the dealer fix this. and I am proud to say besides some very minor brake work and the tuneup the truck has had very few problems...except a small leak around the back window when it rains very heavy that the dealer did not want to fix.

Anyway Here recently the 4x4 has not worked correctly. It has the shift on the fly with the handle on the floor which resembles the older trucks...however you can put it in 4x4 while you are going. This has worked well in the past but recently it will not work properly. I went to the dealer and they said something is worn on it and basicly took my $25, They said they hooked the 4x4 up to a computer but I am not sure if they did that or not.....They did not spend much time on it I know it was in and out...I was willing to spend money but they acted like they were not interested....It must be good to have enough work not to care......I was not happy with them....they charged $260 to change plugs and wires and would not help much with this 4x4 problem a couple weeks later. I also have trouble with the blinker not working sometimes and he said that you have to tear apart the dash to fix something...I thought it was a flasher.....I dont know what to think of them...part of me beleives them part of me does not....I hope the forum helps me find out...

I could not get the truck to go into 4x4 on most occasions...sometimes though you can start it and it goes right in and the light on the dash comes on and it works fine......however it seems once the truck warms up or maybe moves and you go to put it in nothing happens...no light nothing.....sometimes when it is cold or not moving nothing happens either....it is not working more than it is working.....

The mechanic showed me how to get it to light up everytime today...he jerked the lever very hard and all the way to low and it works everytime while stopped. I dont think he could get it into high but he claimed to. He thought it was a worn fork...but honestly the 4x4 was not hardly used on the truck and with it working sometimes perfectly and then othertimes not (or maybe to low with the rough method which I hate)....so I thought it might be something simpler

So that is what is going on with it....They said they checked the two solenoids and all......Could this be vaccum or a motor that engages it....Any help is truely appreciated....I really would like to fix this....Also how dependable do you guys think this truck is with 135000 miles on it? It looks great and runs perfect now but I actually thought about selling it due to the
4x4 and age although I still like it.....I really hope you guys can help me out...I am not an expert so you will have to keep down the technical talk (or explain what you mean!) I really appreciate any help....it will help out my old friend my 98 truck!

 

That's a lotta words right there. 135k on a '98 is low miles. That girl has a bunch of miles left in her. Can't help much with the 4x4 problem, other than try to find a reputable tranny shop that knows 4 wheel drive. I don't understand why the dealer wouldn't fix it. Did they even quote what the repair would cost?

 

No quote no nothing....they almost acted like there was nothing wrong and I was less than dirt.....I will not go back there. Good to here that it will run for a while! I dont have the cash to shell out for a new one but I was ready to sell it today...I think it was more the dealers attitude than the trucks fault. I realize it is getting older...I sure hope I can get some help with the 4x4 problem! Thanks

 

I have the same problem...

 

Go to a smaller tranny shop. Stealerships are are a waste of time and money. My bet is its a solinoid/switch that isnt working properly.

 

How could I check these. I read on the forum about vaccum lines and a diaphram on the front of the transfer case. I checked the fuse it is getting power through it even when the thing will not work.
Funny thing I drove yesterday and after I started I tried it and it worked perfectly no jerking it in or nothing...it worked like it used to then i kicked it out and going down the road i tried it again...perfect again....I dont see how a linkage would do this like they said. If I knew how it worked I think I could replace some parts like the solenoids, diaphram, vaccum line...etc...but I would be shooting in the dark unless I knew how to do some tests and rule some stuff out....Hey was this not the dealers job? Also would a tranny shop know about the on the fly electric or whatever stuff?
Any help would be great....If I knew what to test and how to do it that would help

 

Alot of tranny shops also deal with differentials and transfer cases. If you look around the forum there are a couple threads about troubleshooting the 4x4 problems. Cant really tell you too much myself Ive only dealt with the old school manual systems

 

pick up a haynes manual that has basic troubleshooting tips. check your transfer case fluid. all the vacumn hoses.,maybye your linkage is binding. my old dakota was doing the same thing. also make sure your slip splines are lubed. best way to find a good tranny shop is ask around.

 

Looks like other people are having this problem...I just found the search button...I was looking only at recent posts....There is lots and lots of info here! I am new to this forum so I missed that seach button and was just looking at recent ones....It seems like the two solenoids should have vaccum one at a time and not both at the same time. Also I need to lube up the acutator shaft....that little thing behind the cover on the front of the transfer case.....I am thinking that I might replace both solenoids and the little motor or whatever that kicks in the acutator shaft. from what I read that should fix the problem as long as it is not the shift fork that is broke. Also what oil goes in the transfer case? I might change that as well.....Funny thing is when it is cold like tonight it works perfect. That has to be in those solenoids........I hope.....When it kicks in you can hear a noise from the glove box...a click...is that the solenoids I hear or is there another part on this? I really like the front axle setup on my 70 amg military deuce and a half.....it is air operated 37 years old and works perfectly! But it seems like the Ford might still have a simple fix...at least I hope so!

 

I have the manual 4x4 also and it would only work sometimes if at all. I did some research here and replaced my oil switch/four wheel drive indicator switch. Got that at the dealer. Its a real easy fix, just unplug the old one and use a long sockt to get it out. Just follow the linkages from the floor shifter underneath the truck and should be close by. Worked for me.

 

Is this part correct for the shift on the fly? also does it mount on the transfer case? Thanks again for the help!
Also I oiled the shaft that engages the front axle and it seems to work a little better....what does this turn inside the case? This is a great forum I think with a little help I can fix it!

 

All four wheel drives are "shift on the fly" now a days. Yup, that part is on the transfer case. Just follow the linkages from the floor shifter underneath the truck into the transfer case. There are wires running to it you can unplug. In a way I hope thats your problem cause its an easy fix.

 

I will give that a try...Thanks So Much

 

 

NMC please let eveyone know if that fix works for you, I have a 2002 with only 75,000 miles and have the same problem. Mine works more often than not but seems to not work when i really need it.