Help Diagnosing 4x4 Problem

[quandary]

I just noticed that the back end slides out when turning this winter. The truck goes from 4x4 auto to high when this happens.

As a test, i stayed in 4x4 high and went around the corner again with a fishtail. There are no flashing lights and the 4x4 seems to shift from auto to high to low.

I took it to a transmission shop and they said the truck drives like this and wanted me to buy new tires after a road test (no diagnostics).

1) Is there a way to test the 4x4 controller module? I replaced it 2 winters ago.

2) Is there some other computer diagnosic that would help diagnose the problem?

3) Is there a way to measure or see if there is the right amount of power applied to the front tires?

4) Do i simply accept the statement that this is how the truck drives and buy new tires? The tires are all-seasons with good tread. I would expect that the truck would still not fishtail.

 

[MarkM]

You've posted this in the 2011+ section my friend.

 

[peterk9]

Moving thread to proper forum.

Peter

 

[Sweersa]

I just noticed that the back end slides out when turning this winter. The truck goes from 4x4 auto to high when this happens.

As a test, i stayed in 4x4 high and went around the corner again with a fishtail. There are no flashing lights and the 4x4 seems to shift from auto to high to low.

I took it to a transmission shop and they said the truck drives like this and wanted me to buy new tires after a road test (no diagnostics).

1) Is there a way to test the 4x4 controller module? I replaced it 2 winters ago.

2) Is there some other computer diagnosic that would help diagnose the problem?

3) Is there a way to measure or see if there is the right amount of power applied to the front tires?

4) Do i simply accept the statement that this is how the truck drives and buy new tires? The tires are all-seasons with good tread. I would expect that the truck would still not fishtail.

My 2005 XLT 4x4 in 4x4 Auto will engage 4x4 automatically when it detects rear slippage, then disengage when slippage stops. It shouldn't automatically go into 4x4 High or 4x4 Low and stay there until you take it out of it. You have to manually push the buttons to keep them in those states (4x4 Low is a little different, you have to be stopped with brakes on, in neutral to get in and out)

When I attempt to drift in a snow covered large parking lot (only did it as a test) the 4x4 Auto engages the 4x4 and disengages when the rears stop slipping.

The Explorer is always in 4x4 Auto when you don't put it in 4x4 High or Low with the buttons. All of this is by design, if I'm not mistaken. Is your Explorer behaving differently?

 

[quandary]

Yes. It behaves differently. When in 4x4 auto, it detects slippage and then goes to 4x4 high. Once in high, i have to press auto to get it to go back. I accidentally did a full donut on a curved road yesterday. The truck is definitely not throwing power to the front.

A friend suggested to me that the front end actuator or mechanical switch might not be working since I did replace the 4x4 controller module. (I don't know a lot about transmissions.) Are such components serviceable from underneath without pulling the transmission?

Do you know of a way to test the 4x4 controller module? That is what i replaced a couple years ago and it fixed it. I wanted to see if there was a way to rule it out as the source of the problem.

 

[4WDriver]

The electtonic shift actuator is in fact replaceable without dropping the transfer case. You will need an electrical connector pin removal tool to get the individual wires out of the large connector they are part of. Unless the actuator has been replaced before, and whoever did it put the wires back in the wrong places on the connector, your problem doesn't sound like the actuator is at fault. I would think if it was, your 4x4 light would be flashing, indicating the module has detected a fault in the system. However, and incorrectly connected actuator could possibly damage the control module.
It sounds a lot more like yet another faulty shift control module. Make sure you disconnect your battery when you do this as well as making sure not to touch any of the connector pins on the module with your fingers. The control modules can be damaged by static electricity. What your vehicle is exhibiting is non-designed operation. It should not constantly light 4x4 High indicator unless you have selected 4x4 High. That is what causes me to think the control module would be at fault.
The best easy way to check for front wheel engagement in 4x4 Auto is to get on a dry dirt road, come to a complete stop, then accelerate hard. You should feel the rears spin, then hear a clunk and feel the truck just take-off. If you just continue spinning tires and don't feel throw-you-back-in-your-seat acceleration, the fronts are not engaging. You could also try this in the other modes (4x4 High, and 4x4 Low) and you should not have any clunk, or spinning wheels, it should just GO.
Also, remember these systems are part-time 4-wheel-drive systems. There is no differential in the transfer case that would allow the front and rear driveshafts to turn at different speeds. When 4x4 engages on these rigs, even the auto 4x4, the front and rear driveshafts are locked together. This can actually cause a spin-out in icy/snowy or wet conditions when turning tight corners since the rear can't turn slower than the front like it needs to.
If you have any other questions or need me to clarify anything I said, just ask. I'll be glad to help.

 

[guy48065]

...Also, remember these systems are part-time 4-wheel-drive systems. There is no differential in the transfer case that would allow the front and rear driveshafts to turn at different speeds. When 4x4 engages on these rigs, even the auto 4x4, the front and rear driveshafts are locked together. This can actually cause a spin-out in icy/snowy or wet conditions when turning tight corners since the rear can't turn slower than the front like it needs to.
If you have any other questions or need me to clarify anything I said, just ask. I'll be glad to help.

I'm new to my Explorer--and to Ford AWD. In the snow this truck feels very different from my 05 Durango it replaced. I got stuck in deep snow last weekend and noticed only the 2 tires on the driver's side were spinning--even though I was bottomed-out and there really was nothing much grabbing the passenger-side tires. When I tried 4WD Low the light only flashed and never engaged (although in the heat of battle I'm not sure if I was in Neutral or Drive when I pushed the button). In Auto when the tires spin the 4WD High light stays on, then goes out when traction is restored.

I don't know if this is all normal or not and the manual is very vague. Also regarding the bolded quote--the manual states when in Auto there is 15% drive power transferred to the front axles. Is this marketing BS or is there a fluid-type clutch that allows this without causing rapid wear on dry pavement?

 

[4WDriver]

Guy48065, the answer to your question depends on your specific Explorer. These vehicles could have been equipped with either Auto 4-Wheel Drive (A4WD), or All-Wheel Drive (AWD). I don't know a whole lot about the all-wheel drive setup, but imagine that one could be applying a percentage of torque to the fronts. The A4WD does not do a percentage, it is either engaged, or not engaged. The controller engages it only for the minimum time required to remedy the rear wheel slippage and then goes back off. Under normal conditions (no rear wheel slippage detected) this system does not apply ANY torque to the front. I can't say for sure about the 4x4 High light coming on when in 4x4 Auto and it engages the front due to rear slippage, then goes back off when it stops slipping, I have not paid that much attention to it. I will have to check that out...
When you noticed only the 2 wheels on one side spinning, that is normal, you have open diff's in the axles, so the wheel with the least traction (easiest to spin) will spin. Only with lockers in your diffs will you actually spin all 4. As for the flashing 4x4 Low light, that is indicating to you it can't complete the shift due to some error, which in this case, was probably you not having the vehicle's wheels at a complete stop, the gear selector in neutral, and your foot on the brake until it completes the shift.