Hey guys My name is Jonathan and I'm new to the forums. I have a friend who drives a 2002 Explorer 4x4 with around 148,000 miles. I searched online and found out that these trucks have problems with the 4x4 system engaging & disengaging. I drove the truck today and from what I could diagnose the 4WD High engages when you press the button, but when you press the 4WD low button the light doesn't come on in the dash board. Also after driving the truck for about 5-10 min your hear & feel a load thunking noise coming from the transfer case as if its trying to engage 4WD but can't fully. When you stop the noise stops until you begin driving again for a few minutes. The transmission shifts fine, so I wanted to know if anyone has had these symptoms when the 4x4 control module is bad or if the 4x4 module that is in the glove box is bad.

Thanks for the help,

Jonathan

 

Welcome to the forum

Sounds like you are new to 4x operation.

NEVER engage 4x4 on dry surfaces, use only on loose/slippery surface. What you are experiencing is wind up and if you continue it will cost many $$$$ to repair...

You need to tell us what type of transfer case you have before we can further advise.... Philip

 

Ok, thanks for the quick response I will find out and let you know

 

Also where would I find the model number for the transfer case?

 

if you have a 2002 i would expect it is the auto 4 wheel drive. you selector should say hi- lo- and auto. leave it in auto all the time. the computer will decide when to use the 4 x 4 mode.... you can put it in hi or low when off road.

 

I found out that it is a Borg Warner 4411 Transfer Case, if anyone can point me in the right direction from here on how to diagnose any possible problems with this model I would greatly appreciate it.

 

First and foremost RTFM, I would be willing to bet that you can only put the transfer case into 'Lo' when you are in neutral or park, with the brake fully on. It is a safety feature installed in automatically actuating transfer cases to try to make sure that you don't damage yourself or your truck. Also, without a more specific description of the problem, I'm not sure how much help we'll be.

Questions:
Does the check engine light come on? If so, have you pulled the codes? When you have the 4x4 engaged, what surfaces are you driving on? Can you describe the 'thunking' more specifically? Does 4x4 disengage smoothly? How does that work/feel? Do you have jackstands, or could you retrieve some?

Suggestions:
(be careful when undertaking any tests, as most of what I personally do is dangerous and at least partially insane, and as such I take no responsibility for any injuries incurred while performing suggested maneuvers.)
To see if you're transfer case is in fact engaging, you could pick your truck up off the ground through use of 4 jack stands, [do this only on a level surface and with the vehicle pointed in a safe direction], then start the vehicle and put it in 4x4. the tires will spin slowly in 1st gear w/o any acceleration. If the front tires move, grats, you have 4x4, if not, then it could be a problem with the transfer case, or and linkage downrange of it.

Also, as was previously mentioned, when in 4x4 mode, you essentially 'lock' the transfer case, forcing the front and rear drive shaft to spin at the same speed always, which on hard surfaces with high traction will lead to axle windup, which will eventually severe damages to your vehicle. Wind-up occurs because the total distance traveled by each axle is different, and without spider gears or a clutch pack setup between the two axles, tension is generated on hard, dry, high traction surfaces. When that tension builds up, you get a sudden release as the tires of one axle 'hop' or jump, which to me sounds like your issue.

You might also find this useful: http://www.rsgear.com/articles/2008_05.pdf

 

Caveat: I am by no means an expert on anything; and if I offend, confuse, or get anything just plain wrong feel free to call me on it.

 

First off, was there any resolve to the issue described in this thread?

I have been having the same issues with my wife's 02 Explorer. While driving if you decelerate, the transfer case tries to engage the 4wd. This causes a whining noise and you can feel the vehicle jerk like the 4wd is engaged or is trying to engage. If you can stay in the throttle to keep a load on the drivetrain the problem does not continue. The moment that the load is taken off the drivetrain the transfer case will try to engage. If it does engage (at speed) it will not disengage until you come to a complete stop. You can put the transfer case in 4H just fine but 4L will not activate at all. This is my wife's car so no off-roading happens, the 4wd only gets used when the weather is bad and she lets the auto take care of engagement.

Anyone who has experienced this problem please let me know. Thank you in advance for your time and help!

 

Any codes? May be the speed sensors in the transfer.

 

From the description it would seem you have a ControlTrac.

Any differential in rotation between the front and rear shaft will trigger activation while in AUTO..

Make sure the tires are ALL of the same circumference and pressure..
Drain and refill the T/C with fresh ATF, and
clean any filings off the hall sensors...

.....Philip

 

yes my o2 explorer with around the same miles did the same thing. I unpluged the transfer case wire at the rear of trasfer case drives fine now just got to replace 4x4 control module now

 

Was it your tire size? I'm having exactly the same issue. Please tell me what it ended up being

 

I empathize with your problem. I have a 97 Ford Explorer I replaced the transfer case back in 09 with a used one total cost of parts and labor was still $900. Since the case and driveline was from a 94 they had to cut the driveline to fit. Anyway I had the same problem with it engaging, disengaging, bucking, tire skid, noise, jerking, sometimes with so much force that the steering wheel would hurt my hand if I was in a turn. This was going on for 2-3 years everyone had a different guess no one knew exactly. I had the rear wheel sensor replaced on a "guess" paid $150 for nothing. Then I had the transfer case fluid drained and replaced. The fluid was so black and sludgy came out like tar and I wondered if the guys that replaced the transfer case forgot to drain and replace the fluid at the time and my guess is they didn't. After I had fresh fluid in it ran great with no problems, for awhile, then the problem began again so I found a mechanic that did guess what? Took out the front driveline. This immediately solved the problem but also turned it into a 2 wheel drive. The U joints were shot and I imagine the U joints are going bad on the rear driveline as well. He suggested I have the transfer case motor replaced which comes off with four bolts the motor itself attached to a wire harness you unplug the put the new one on same way. Except on my transfer case is a set of two additional wires that hookup to somewhere, the motor is at a reasonable cost but where these two wires go I have yet to find out. Winter is coming so I have to decide whether to keep it a two wheel drive or have my mechanic hook back up the front driveline with new U joints, replace the rear driveline U joints, then drain and replace the transfer case fluid once more although it still looks good. If I start having the problem again then replace the transfer case motor as well. I will keep you posted on this. By the way I drove in Auto most of the time in snow I would switch to 4Low. Switching worked most of time but sometimes not which I think has to do with that motor until repaired. But it didn't matter I was in Auto when I had all my problems with the jerking and bucking and it did it on its own whenever it felt like it.
So I hope I shed a little light: Replace the transfer case fluid add a bit of Lucas Oil to it, doesn't hurt it. Have the transfer case motor checked and also the drivelines. Exchanging the fluid was about $60 transfer case motor can run from $40 on up + checking the drivelines + labor is a lot less than replacing the transfer case and still have the problem.
I will keep an update if anyone is interested if I decide to have the front driveline put back on so I can have 4x4 for winter, and have the transfer case motor replaced as well we will see if problem is solved.
I am no mechanic however and I am sure there are other opinions and other solutions as everyone's problem is slightly different as there are parts and different fixes for similar situations but I am telling what worked for me after listening to too many people trying to tell me too many solutions only so they could make a buck or two me being a woman yet used to work in the auto industry so I was not so convinced and could see the bs with most fix suggestions. Finding a good honest mechanic willing to go the extra mile to find out the cause of a problem from the least expensive to the most expensive in that order is just as hard finding a doctor who will help you! And finding a mechanic who knows Fords is good for a start. By the way I took my problem to the Ford dealership and they told me I needed a new transmission for $1,500+ and would not budge on their diagnosis. Nothing wrong with my transmission at all!
Thanks for reading guys sorry for being long winded and will keep you updated.....

 

Well I ended up finding a solution to this problem. It was 4 different brands of tires with different treads and wear patterns resulting in 4 different sized tires.

What was happening was that the front and rear drive shafts were moving at different speeds as a result of the difference in tire sizes. A difference in size of as little as 1/4 inch is enough to cause the computer to think there is tire slippage and try to engage the 4wd while casually driving down the road. This system cycled at the regular interval of around 105 times a minute regardless of speed, causing the pulsating and clunking.

I tested whether or not it was the 4x4 control module by removing it's fuses under the hood (17 and 18), and the problem stopped. This would have worked exactly the same for you, instead of removing your front drivetrain. I'm sorry you wasted that time and money. What this did was disable 4wd entirely, so I wanted a better solution.

I was confident that the tire sizes were the problem (thank you Google) and I was able to resolve it by playing with the air pressure in the tires so that the center of every wheel was the same height from a smooth level surface (regardless of recommended tire pressures). All pressures landed between 30 and 37 psi, thankfully. This was a temporary fix that was able to confirm my diagnosis and get the truck back on the road.

I brought the truck back to its owner with the suggestion that he purchase 4 new tires as soon as he can afford it.

I hope this helps someone