First, to all, thanks for pin pointing the intermitting problem with my diesel Excursion intermittingly shutting down. It was the Cam sensor.

Next topic: I also have a 97 Explorer and the 4WD does not work. All fuses are good, 4WD selector switch check out Ok. There are no codes of failure code flashing. Any further ideals of troubleshooting this malfunction?

Thanks Forum for your assistance,

rbraxton17

 

OK, you need to be more specific
if it does not engage in 4H, that is a clutch/electrical problem.
if no 4L then it may be the shift motor

 

There is just 1 electric shift motor to actuate 4H and 4L. But we do need more info. I think some 97's were even AWD with 4H lock and 4 L options. So what drive line do you have and what are the problems - what do you try to so and what are the results?

 

4WD does not operate either in 4H or 4L. The selector switch has three positions:
Auto, 4H, 4L

 

OK so you have an AWD vehicle - always in 4 wheel drive. 4 H locks the front and rear diffs to turn at the same rate, 4 L does as well but also uses the transfer case's gearing to drive both diffs much slower but with much more torque so you can drive over Hondas and the like.

When in auto, there is a mechanism that diverts power from rear to front when the front wheels start slipping. Normally ~90% of the engine torque goes the the rear diff. This mechanism I believe is a clutch assembly on the output from the transfer case going to the front diff. Some have viscous couplings inside the transfer case but I think these were used later on Fords like 2001 or 2002.

If you have a clutch assembly, the 4WD auto sensing system controls the clutch by electrical pulses. The more the wheels slip, the more pulses and thus more clutch engagement and more power to the front wheels.

Some people have relayed problems such as flashing 4WD light on dash and have found the wheel sensors or diff spin sensors are dirty and causing erradic actuation of the slip clutch. You didn't mention any flashing lights but if you have that too, this might be the problem.

Again, there is just one electric shift motor hanging off the back of the transfer case. When you hit the dash button, this shifts the T-case into 4W H on the older, non-AWD vehicles. For yours, it probably just locks the slip clutch to full on - as the other poster suggested.

Then when you hit 4 W L button, the electric shift motor moves the T-case on all models to it's low range gearing.

Your system probably has logic that does not allow the t-case to engage low range unless high range conditions/feedback signals are met. So if you fix it to go into 4H, 4L will likely work again too.

I would start with the wheel or diff sensors. The diff sensors, if so equiped, seem to accumulate metal shavings that throw off the signal. Usually they can be cleaned but sometimes must be replaced. Next, I would look at your slip clutch.

 

I am not sure that this is completely accurate and will have to wait until I am home to check my service manual for more details on it. However, I am pretty sure that rbraxton17 does not have an AWD setup. The AWD setup on these model years is a limited slip arrangement in the transfer case and the rear differential (open front diff). That came with the 5.0L in 97 (I am pretty sure that they did not have AWD with the 4.0L). In the AWD version that I have (5.0L 97) there is no electrical monitoring of the wheel slip, it is all based on fluid pressures in the transfer case and the rear differential (which is why the gear oil needs the Ford additive in it).

In any case, I am almost positive that the arrangement that is on the ones that have the 4-auto, 4-hi and 4-lo are usually in rear wheel drive and there is a mechanical engagement of the transfer case (thus feeding power to the front axle). In the case of the "auto" mode the vehicle monitors for wheel speed differences and at a threshold engages the transfer case actuator to kick in the 4WD. Like Jharger described.

When you choose 4-hi or 4-lo it just engages the actuator full time. Apparently the engagement mechanism is one that is prone to having issues on the Explorers and the Rangers as I have read many posts about how it is simply a matter of removing the shift motor and giving it a cleaning it.

I would take a look over in the Ranger forum on this site to see if you can find more information there. I recall seeing a pretty detailed description when my buddy (with a 99 ranger) found when he had a similar problem (no 4WD engagement).

 

Right. It all depends on the viscous coupling (like your V-8 model apparently) or the clutch type. I've read up on both and I don't think the 4.0's had viscous couplings until much later years.

 

no awd have NO switch he has control trac....crawl under truck there are two sensors clean them first and make sure they are hooked up.... the control trac will work but won't lock fully in (my 97 would do this) try to squell a tire if you fell the front kick in then I would guess it a sensor or bad switch (or fuse)butt if you can burn the back tires off then you may have a bigger problem..

 

I have a 96 Explorer Sport 2dr. I have a rotory selector with "2WD". . .4WD auto". . ."4WD low" I just got back from embarassing myself. I tried to pull my sons friend out of a ditch. (17 . . . female . . . wet road ! Need I say more)

ANYWAY ! ! ! I'm in 4WD low . . . I felt it shift to low range . . . I can tell it's pulling lower geared . . . all the signs are there . . . No fault lights . . I AM IN 4WD LOW RANGE.

OK, here goes . . . Tighten the tow rope, accelerate to pull her out . . . ONE WHEEL SPINS ! ! ! ! ! ! ! Left rear to be precise.

What's wrong ? ? ?

Les
NebFlyer@yahoo.com

If it ain't broke, take it apart anyway, just to see how it works.

 

Sounds like the transfer case is engaging the low range gear set but not the 4WD drive shaft. I would hazzard a guess that it is the engagement motor not doing what it is supposed to... seems like a common problem on these vehicles (and the Rangers too!).

 

So the front wheels ae doing nothing? The rear will spin one wheel if you have an open diff. If you have a limited slip rear, then the clutches might be worn. If if hit the brakes a little, this will put a load on the spinning wheel and allow the other side to engage. As far as front, need more info. With your T-case, I don't think it's possible to be in 4WD and not have the front drive shaft spin - comes off of same shaft.