I have a '97 F-150 Stepside 4x4. I have the floor shifted transfer case. I use the 4x4 mainly for bad weather, no real thrashing off road. I got the truck used and the 4hi worked for a very short time but the 4lo worked fine. But w/ the recent snow storm here, the 4lo was having a hard time engaging sometimes. It seems to me the cold had something to do w/ it because it seemed after the truck was warmed up it would engage. Is this transfer case electronically activated? Why is the 4lo working and not the 4hi?I would think if the 4WD was not working it would'nt work in either, but I'm no master mechanic. I really think it's either electronic related or temperature related or a combination of both. Any ideas?

 

SOHC,

Does the 4x4 light come on when you shift to 4hi? When you shift to 4Hi, is the truck able to move forward or does it seem to be in Neutral? When in 4Lo do the front wheels spin?

Regards

Jean Marc Chartier

 

The light does'nt come on when I pull it to 4hi. The truck will move fine even when the lever is in 4hi(Just no 4WD). 4lo works fine most of the time except when it's very cold, once the truck is warmed up, it does great(In 4lo). 4hi does'nt work at all. I do know that when you engage 4lo, the solenoid clicks and the light comes on,engaging 4lo, but nothing at all happens when I pull it into 4 hi. Could it be a linkage problem?

 

I am not sure, but I think the 4WD is electronically controlled, and it may be a bad fuse or something like that. Maybe a short in a wire that causes bad contact when it gets cold. Does this make sense to anyone? Just my $.02.

 

Does the 4x4 light prove out when you start the truck. It should come on for a few seconds. If it does then I suspect the
4WD indicator switch switch in the T-case.
It is located just below the breather on the front of the T-case. There should be a
gray wire and a Light blue/w black stripe wire going into this. Check for corrosion. If present clean the switch and test 4x4. If still no 4Hi; KOEO ( key on engine off) ground the gray wire. The 4x4 light should come on. If it does I would supect the switch. Do you have access to an electrical Multi-Meter? If you do; KOEO T-case in 4x4hi probe the terminals of the switch for continuity to ground. The terminal that connects to the gray wire should have continuity. If it doesn't replace the switch.
Regards

Jean Marc Chartier

 

Does anyone have a JMC/English conversion chart? Lol, kidding. Would a bad indicator switch cause only 4lo to work? I'll check it out as soon as I can find a dry spot to lie on...Thanks JMC.....

 

If the 4x4 does light up at KOEO it means the bulb is not burnt, and that something is not functionning properly in the system.
If it doesn't light up it means the bulb is burnt and must be replaced before we (you) go changing parts for nothing.

FYI; the Manual system shifts the gears into 4Hi and flips a switch to tel the GEM that 4x4 is engaged. Pull the shifter all the way to 4Lo and the the gears change to 4Lo but the same switch now tells the PCM that 4Lo is engaged and it will change the shift points and engine functions accordingly. That switch tells the GEM to engage the front axle as soon as the lever is placed in 4Hi. If the switch is malfunctionning the front drive shaft axle will not engage till it sees the command for 4Lo. If one part of the switch is bad I would suspect the other parts are on their way too.

Regards

Jean Marc Chartier

 

JMC,

I have sort of the same problem, but since I live in Florida, I don't use the 4X4 much, so I keep not looking into fixing it, but since I seen this thread I thought I might ask you your opinion.
When I start the truck the 4X4 light flashes as normal, and it will engage into 4-Lo, with both lights (4X4 & 4-Lo) But the manual shifter is hard as hell to pull down to 4-Hi, and will not engage, even stopped and in neutral (like to shift to 4-Lo) just makes a god awful grinding noise, like it is trying to engage. I am suppose to shift on the fly up to 45 MPH. The '98 I had worked as advertised, and I could use 1 finger and engage the 4X4. I have sprayed the likage with brake-free oil and it works a little easier, but not like it is suppose to.
Could the linkage got bent some how? If so, I can't think of how one would have bent the linkage?
I bought the truck with 57,000 miles 2 1/2 years ago and til 6 months ago it was the wifes and I never drove it, as far as I can remember the 4X4 worked when I bought it, I tried it in the sand, but I did buy it from a dealer (always blame the dealer, not Ford Motor Company) Now thats its mine I am into upgades and mods, no warranty to worry about, I just turned over 100,000 miles and still strong as ever. But I want to go out the guy's and hit the 4X4 trails, so I guess it is time to start trying to figure out the malfuntion, going fast in a 4X4 is cool, espesially when shovies are around, but one has to be able to "get off" the road too.



97 F150 XL 4X4 reg cab long bed, Oxford White
4.6 auto w/ B&M shift kit
8.8 rear end with 3.55 gears
Gutted MAF and custom air intake tube
75mm BBK throttle body (match ported to intake riser)
True Dual exhaust w/ Dynomax race magnum bullet mufflers
Exiting before rear tire on passenger side
Auto Meter 3 3/4 dash mounted Tach
8mm Beldon wires
Progressive rims w/ Kelly MSR 285-75-16
Toolbox
100/110 super white headlights
60/40 seats from a '99
12 disc JVC changer and head unit


Future mods……

Electric fan
Under drive pulleys (have on hand, waiting for the elect fan, tear it apart once)
Headers
Accel coil packs
Jacobs ignition box
Superchip----(have on hand, but needs custom program for my comp.)

 

my97,

if the shift linkage is jammed or bent it can be difficult to engage 4x4. Suprizingly if it is loose the same can happen trying to engage 4hi. As you know to shift past 4Hi you have to push towards the left because you are up against the stopper for the 4hi position. If the linkage is loose it can come up against the stopper before 4Hi is fully engaged, which will cause a grinding of the gears till they pop into 4hi.
When trying to shift into 4hi and it grinds, try partially shifting into neutral to see if it pops into 4Hi. You don't have to go all the way into neutral just ½ way to see what happens.

Have a close look at the linkage to see if it is loose. A critical point is were it connects to the shift lever on the T-case.

Regards

Jean Marc Chartier

 

The 4x4 indicator light works fine. It comes on when the 4lo is engaged. So, if I'm following correctly, 4hi and 4lo each have a switch for the GEM module? And you suspect the 4hi switch is gone and the 4lo switch may be going too? Where are these switches located and about how much $$ for each? Thanks a lot for your help JMC, you're dang good...

 

SOHC,

The same switch is involved, it is more than a simple on/off, it has more than one position. Off, 4Hi and 4Lo.

Regards

Jean Marc Chartier

 

Where is the switch located and how much $$ is it?

 

SOHC,

It is located just below the breather on the front of the T-case. There should be a gray wire and a Light blue/w black stripe wire going into this.


JMC

 

JMC,

I looked under the truck and all the linkage seems tight to me, I had my neighbor shift through it a few times as I watched, to me it looked like the linkage was working, but I have not seen what it is suppose to do either.
so, the linkage does not look/feel loose
the lo will engage and get light in dash
the hi will not engage and gets no light in dash
the hi light in dash is not burned out
the more I play with it, the lever moves a bit easier, but still not like it should

How do I find out if it is hitting the stop before it engages to hi?

could the likage have corroded up and someone "muscled" it and bent the linkage so it will not travel far enough to get 4-hi to engage?

Any other suggestions????

Good news, I found the exhaust leak that was driving me nuts. pin hole on the weld the where the y was removed. now just to have the guy that did the exhaust hit it with the welder.

 

I have the floor shift 4x4 and the only way it will stay in 4x4 hi is to move it left and then back to the right, Like you have to do to put it in 4x4 lo. Are you suppose to be able to drop it straight from 2x4 hi to 4x4 hi by just moving shift straight down?