I hope that someone has come across this issue.. it shows in the instrument cluster that its in 4Hi when I switch it to it, but its not engaging all four wheels. Does the same in 4Lo.. it worked just fine all winter and was working fine this morning, but when I went out to lunch I put it in 4Hi and..... nothing back wheels spinning but nothing up front. I only have 26k mile on it and have only had it for four months, bought it with 18K on it.

Also its an automatic..

Thanks!

 

I have seen this a lot before. It is usually the selector motor on the transfer case. Have someone get in the truck, and switch from low to high. Put your hand on the motor that is on the side of the transfer case. If you ca feel or hear it move, then unbolt it. Do the same again, and see if the shaft turns. If not, bad motor.

Chad

 

Thanks! for the info, I will give that a try tomorrow.

 

If the instrument panel light is on, then I'd think the transfer case is shifting as expected. Sounds like the front hubs are not engaging.

With such low milage, I'm assuming you have the latest generation 150. If so, you probably have an issue with the IWE (Integrated Wheel End) system, either the vacuum solenoid or the IWE actuators themselves. The IWE's should engage when the engine is off. If you can spin either front wheel shaft with the engine off, the IWE in that wheel that has a problem. If neither spin, it's probably the vacuum solenoid. Hope it's the solenoid, much cheaper to fix.

 

Would this also apply to a '00 Lariat, 5.4?
I nearly got stuck in my own driveway this morning on a couple inches of fresh snow. I tried for 20 minutes (while I was driving to work) to get the front end to engage, but nothing.

Are there "Rules for engagement" so to speak? Someone told me the front end wouldn't engage unless in a forward gear. My experience is that I need to be moving before the wheels lock up ( when it was working). Is this right?

Thanks very much. I need to get this fixed before I start down the bush to collect firewood...

 

Ok, this applys to the '97-'03 ('04 heritage) trucks.

When you turn the ****, the transfer case is shifted by a motor and also a vacuum pulse locks the Center Axle Disconnect.

Easiest way to check the transfer case motor is to first try 4H, and then try for low range. 4H can be obtained in any gear, and 99% of the time, a light on the dash means a completed shift. To shift into low range, you must be stopped, in neutral, foot on brake with working brake lights. Again, a low range indicator comes on after the shift is completed. Also only moving at half speed in Low range indicates a working transfer case. Finally you could have a helper watch the front driveshaft turn as you move.

If all that checks out, and the front wheels still don't pull, you're lookin' at a failed CAD, vacuum leak, or bad vacuum switch.

Adrianspeeder

 

I have the same problem. For me it started last summer when I attempted to pull the boat out of the lake. It showed it was in 4wd on the cluster but wouldn't go into 4wd even after several attempt. I ended up getting a tow truck since it stuck by then. Supposely, it was a vacuum line off one of the hubs. They put the line back on and cleaned out the actuator. Ever since then sometimes it will engage in 4wd, sometimes it won't and even sometimes it takes a while. I've been back to the dealership twice since then after it had an episode of not going in but by the time you get an appointment she usually has corrected itself. I'm convinced that it is a lazy switch or there is still dirt in the system of which the dealer doesn't know how to fix. This time they're wanting to charge me because they can't find the problem. The bottom line is that you can't depend on the 4wd at all which makes it pretty well useless because when you find out that she won't go into 4wd, it usually too late, your stuck.

Totally unsatisfied with my 2004 F150 !!

 

Howdy and welcome. Your '04 has a different setup however with two vacuum locking hubs. Same problem outcome, but a different mechanism.

Adrianspeeder

 

i have an opposite problem mine actually goes into 4hi and 4lo but going into 4lo there is no light just the regular 4x4 light no 4x4 low range light that comes on it came on once tho. but going back into 2hi my 4x4 light stays on (although i am in 2hi) and doesnt go off until the next morning. my uncle told me it was my sending unit in the transfer case so if someone can tell me where it is and how to take it out that would be great. any help would be greatly appreciated.

 

O.k....so this is me

This is what happens for me, yes...I move at half speed. If I try and light up the tires (in my yard), the rear end of the truck kicks out. I'm not getting front end help at all. All I hear is a "click sound" from behind the instrument cluster. It's been a while but I thought there was also another noise over on the passenger side, but I don't hear that anymore. I definately don't feel the front end hooking up. Usually I would feel a slight clunk as things locked together.


The dash light comes on ( for the 4wd), and when correctly shifted the LOW RANGE light come on also. A noticeable clunk as things switch over into 4L.

I had the front end off the ground last year when I first noticed it, the front D/S can't be turned by hand when 4H/4L is engaged, it spins free when in 2H.

I guess there is no problem determination/ testing that can narrow it down to one or the other short of substitution?

THanks...
Steve
Huntsville, ONT.