4-wheel drive knob help

[ned032002]

The knob that turns on and off the 4 wheel drive, what does AUTO mean and do? See I'm having issues with mine at the moment (well I think I am). Help

[shorod]

Do you have the owner's manual? If so, there should be a description in there. If not, you can download a PDF copy of the manual from Ford's website.

According to the service manual:
The C-Trac transfer case transmits torque to the front wheels through an electromechanical clutch assembly. In the Auto mode, while at rest and under cruising conditions, the Generic Electronic Module (GEM) activates the transfer case clutch at a minimum level. This allows for the slight difference between the front and rear driveshafts which occurs normally when negotiating a corner on dry pavement. Under any of the following conditions, the GEM will increase the torque sent through the clutch to the front wheels in order to prevent or control slip.

l Slip is detected (by monitoring the Hall Effect Sensors in the transfer case)

l Heavy acceleration (by using the throttle position signal from the EEC)

l Very light or zero throttle at speeds above 64 km/h (40 mph) (using the throttle position signal from the EEC)

-Rod

[ned032002]

I've notice a couple of times in the last couple days when I go to take off from say my parking spot, it seems like when I'm turning the vehicle is acting like it's in 4 wheel drive but the knob says AUTO. And when in a slippery position on AUTO all 4 tires are spinning but the 4 wheel drive indicator light is not lit. So what do you suppose the problem is. Is the 4 wheel drive kicking in so the vehicle doesn't spin it's tires on a step grade covered in snow or ice?

[denisb]

If your vehicle is parked in a slippery spot and when you take off the vehicle senses that a tire is slipping it might be engaging the clutches making it feel like it's in 4x4. If you take off slowly, without slipping or agressive takeoff, I would say you'd be able to notice the 4x4 engaging. But mine doesn't have auto, so I can't say for sure.

As for the 4x4 light I think it's just an indicator to tell you where your shift button is set, so it probably wouldn't light up unless it actually was shifted to 4x4. That should be in your manual tho.

What year's your vehicle, if it's the same as mine I can look it up in mine if you don't have a manual.

Denis

[ned032002]

I don't have a manual and I haven't yet downloaded the one available, also mine is a 98.

[denisb]

Mines a 2004 and looks like the auto 4x4 was not available for that years or not available on the Sport Trac because it isn't listed in my manual.

Sorry,

Denis

[shorod]

The manual indicates that the 4WD light should come on when the Auto mode engages 4WD.

I've seen quite a few of the transfer case motors for sale on eBay and read that they are a fairly common item to fail. Maybe your motor failed and the transfer case is stuck in 4WD.

-Rod

[denisb]

I've heard of the 4x4 switch/module going bad but I think it will usually do the oposite and keep your 4x4 light on all the time.

Definately looks like you have to get that checked tho. Because if it is stuck in 4x4 (binding up when you turn) it's probably not good on your drivetrain, specially on dry pavement.

Denis

[ned032002]

Luckily there's snow everywhere but I will get it in to get checked asap, just out of curiousty how much does a job like that cost? I'm assuming near $500