will my 2001 expedition still run if i unplug the shift motor?

 

Absolutley. It will just stay in whatever range it was shifted into (2x4, 4 hi or 4 low). No harm, no foul.

 

Greasemark thanks.
I took it to a small shop he said not the trans, put in a sensor for $100 after 2 days started again went to a ford dealer said not the trans but the shift motor because the truck runs great when unplugged. new shift motor $716. 2 days later same thing. Another ford dealer, inspection $376 said need new trans $5760. I said no. I will take Greasemark advise and unplug the Damm thing.

 

For the sake of the pool of knowledge we're building here, could you please share with us what problems triggered your question? What was wrong with the truck?

Thank you!

 

I am not sure of the connection .
The mechanical problem appears to involve the transfer case.
Maybe greasemark can shed some light on why they wanted to install a new trans.
Maybe the kid's teeth needed braces I don't know.

 

Hanky, of all the people that would ask of the connection, I just can't believe it would be YOU! You're above reproach in just about every other case...Oh, what is the world comming to.
4x4 problems can manifest themselves as transmission problems in several ways. Since this powertrain uses something akin (and not much more durable then) a power window motor (which is susceptable to wear, use, and dirt, among other things), they usually (NOT always) get stuck into a range and not shift (or ever shift again), or get stuck between ranges.
Not known to a lot of people, there is a manual section that can be attained that resides betwixt 4x4 high, and 4x4 low that the t-case must shift through to get to either range. This can very, very easily be misdiagnosed as a trans that just won't engage, even though it's fine.
But, i ALWAYS give people a way to defeat me (it makes it fair, Hanky). If I'm wrong, here you go.
A t-case can be thought of as a very simple gear-changer (similar to a manual trans that's acutuated automatically); hence why you can change on the fly into 4x4 high, but NOT low range (which requires stopping to engage the planetary system and will destroy the t-case if done by a mechanical faliure). If you take off the shift motor (or even let it hang), which is easily accomplished by removing the 4 10mm bolts, use a pair of pliers to rotate the little triangular rod that pokes through to the corresponding range (it's usually stamped onto the case). First is high, then the neutral range (it will get easy there), then low range. It may be a little rough (especially if in park or the driveshaft is bound, like it's parked on a hill). You can then start and move the truck a little (not too far in low range, as this causes a lot of windup) to verify the t-case working (or not).
I have big shoulder, and can accept that I'm wrong, but this will be the easiest way to delineate between the trans and the t-case being a problem.
Also, there are usually 2 sensors (input and output shaft) that must work, and caused many problems; I know it sounds like a bit of a waste, but they're inexpensive and I usually replace both at the same time; i've had so very many that I've replaced one, only to come back a week later needing the other one.
One quick test you can do is put someone into the car (key on, eng. off) and while they're shifting it into 4x4, smack the motor smartly with a Hammer; if it goes, it's the motor that's just getting tired (don't beat the motor into submission, just a whack will do. The same is done to jammed starters). If you're sporting about it, and since you've nothing to loose if it responds, then the motor is usually needing replacement. You can take it apart and shine up the commutator and seal it back up (rtv sealer works well here), and it might come back to life and work for a while, or not, depending on the problem.
If the little rod that pokes through turns too easily and doesn't feel like it's doing anything inside (which happens sometimes), then there is an internal problem. If it's jammed, and won't move, it's internal (don't force it too much).
Hope this gives you a direction to go in. And if you can shift it manually, DON'T leave it in 4x4 until you get it fixed; this causes driveline windup and really will cause major problems.
And if you think this hard to diagnose, then wait till you work on a DSP six speed (the automatically shifted manual that's in the new Fiesta and Focus). They're REALLY tough to figure out.

 

Thank you for the vote of confidence, even if it isn't deserved.
What was puzzling me was , if as stated leaving the transfer case in hi, the trans worked as designed and intended. Aside from an electrical information transfer from the transfer case to tell the trans where it was, why would a proper functioning trans need to be replaced?

Come on , greasemark
you gotta be puttin me on.
You can't fool us, we know you are a transmission expert ,EVEN, with the six speeds !

 

Ok, like I always said, I can still stub my toes with the best of them!
In this case, there's a really high degree of probability that there is a huge wiring problem; that explains why it runs great when disconnected. When connected, something probably feeds back and creates the problem.
These are not the easiest systems to work on, and even when they have simple problems, they take a while. The customers chances of fixing this on his own aren't really good, and even if I had it, I might not be able to.
I would imagine that since the Signal return circut goes to the trans and the shift motor (it's basically the PCM's own, seperate ground circut), that this is the problem. I had a very similar problem with a 02 Xpedition, where there was 12 volts running around in the Sig. return, which created really weird problems and something not far from this. Of course, being a "PRO", I thought it wouldn't be that hard to figure out. Was I wrong! Since there are only about 33 diferent connecxtions to sig. ret. on this truck, I had to go through them one at a time. It turned out to have a short in the loom, behind the intake manifold. It only cost about 5 bucks in parts, and about 11 hours of labor, but it was fixed.
This system needs a scanner attached to it to see what's being commanded and what's actually happening. That's really the easiest, best way to diag this.
And I'd bet that it's a high milage unit without having had the benefit of meticulous maintanance. That's why it might just to be better to live with the devil you know, rather than trying to turn it into an angel.
Besides, Hanky, you're one of the few people that I can talk to on my own level without sounding condesending or arrogant. I don't have the advantage of bouncing ideas off my father anymore, and somehow, you understand cars very much like he did. I solved a lot of tough problems with his advice. Besides, you think of just about everything I do, and make it sound fun.
I don't have that ability.

 

Greasemark , are you sure you weren't a psychology major ?

 

No, I wasn't but my father was. He was two really good things in his life: an excellent mechanic (which I follow in his footsteps), and an excellent salesman. I couldn't do the latter, so I chose the former.
I've always worked better with things then with people. One of my many limitations is life, but I've learened to live with my choices.