Transmission or something else

[Miles Walcott]

So here’s the situation. I was driving and then out of nowhere I lost all gears and then when I tried to put the expy in park, it makes a weird grinding noise and with rolls by itself (bad e brake). Only codes I pulled where for a wheel speed sensor which has be a thing for a while.

At this point, I can push the car even when it’s in park, the speedometer moves when I press the gas (it will go to 40 mph but I’m still sitting still), and the expy recognizes that I’m shifting into gear but doesn’t move. It’s like I blew the transmission in all gears. At a loss on this one…already bad enough that it’s stuck in a sketchy parking lot. Did she die at 278k miles?

 

[SafariGoneWrong]

First thought is since you're seeing a speed indication tells me the transmission output shaft is turning. You'll want a helper or remote camera to see if the driveshaft is spinning while you shift through Park, Neutral and Drive. I'd look closely at the driveline from the point where the driveshaft couples to the transmission (is it 4WD? Then the transfer case becomes a variable...) to the differential and both rear axle shafts. Being push-able in Park tells me the driveshaft is no longer connected, so to speak, to the rear axle shafts, assuming the Park system in the transmission is working correctly. An axle shaft that has let go or failed (it's happened to me in a VW) will render you stationary with similar symptoms. Of course, and maybe most likely considering your symptoms, the differential itself could have failed internally. The grinding noise when attempting Park can be explained by the output shaft spinning and the parking pawl skipping over the indents in the parking gear attached to the output shaft. If there's no rotational resistance in the driveline the output shaft should still want to turn anyway while not in gear.

 

[Miles Walcott]

The transfer case is disconnected only because it’s broken, but that’s starting to make some sense

 

[Miles Walcott]

the drive shaft isn’t spinning at all. And it sounds like something is broken under the truck. Almost like something came apart in side the transmission

 

[Miles Walcott]

I retract my previous statement. It spins when I try to push it. But doesn’t do anything when in gear

 

[SafariGoneWrong]

The speedometer showing 40mph seems to say an output from the transfer case is spinning but not the driveshaft as you have shown. I’m not near my XLT or shop manual and not sure exactly where the speed sensor is located, I’ll be checking when I get home. I know exactly where it is on my BW1356 transfer case in the Bronco. @whtbronco has recently had his transfer case apart and might have more insight into mode of failure, assuming that’s where the driveshaft and transmission have become uncoupled. Our Expeditions don’t have a Neutral selection in the 4 WD system, unlike a Bronco, but maybe you have inadvertently found it. Last thought, FORScan Lite can show the commanded gear selected in the transmission. I wonder if you put it in Drive it will show a progression up from 1 through 3. 1 is the default reading if you are in Neutral, Park or Drive while stopped.

 

[whtbronco]

So the the truck is not dead, the engine still runs and transmission is still shifting. The speed sensor is on the transmission output shaft, driver side rear of transmission, pretty much right behind the gear range selector. Here's a diagram I dropped in another thread in this forum yesterday.




So to me it sounds like the transfer case has failed and you stated it's broken. If the chain breaks or the output shaft breaks you'll get no power out to the driveshafts. So maybe the place to start is what is wrong with the transfer case that led to disconnecting it?

If the driveshaft broke part of it would likely be swinging into the ground and the floor pan and making crazy amounts of noise and/or it would fall out of the transfer case. So I doubt the rear driveshaft is the issue.

The other option I can think of is I have experienced what you are when I broke the pinion shaft in the rear diff of my 79 Bronco. Course in that truck I pulled the rear driveshaft out, put it in 4wd and ran front wheel drive until I rebuilt the 9" 3rd member. Can't do that with the Expedition sadly.

The weird grinding you hear when trying to put the transmission in park is most likely the parking pawl trying to seat while the output shaft is turning. Shut off the engine and then out it in park as needed and that issue will be resolved until the failure is fixed.

If you're interested in the transfer case, internal pics and how it works this thread has some info starting on page 3 and lots of pics that start on page 4. I rebuilt my transfer case in my quest to eliminate vibration.

Not so Good Vibrations

Thanks SafariGoneWrong, that was interesting and a bit different than my AllData info. I thought the clutch was only used in AWD, it looks like from that the clutch is engaged intermittently in AWD and basically fully/constantly engaged in 4H and 4L. I've only done a bit of troubleshooting...

www.expeditionforum.com

 

[Miles Walcott]

So I guess I’m trying to figure out is if it is a broken output shaft how do I replace it if I can replace it?

 

[Miles Walcott]

Also, the shaft for the transfer case was removed when I had to get my flywheel replaced. The transfer case was already broken so they left it out

 

[SafariGoneWrong]

Can you send a picture of what you have aft of the transmission? I think we’re going on the assumption you have an OEM 4WD configuration but now I’m not so sure.

 

[Miles Walcott]

It’s OEM.

 

[whtbronco]

The transmission output(tailshaft) shaft will require removing the transfer case or the 2WD tail shaft housing to inspect. Replacing it basically requires rebuilding the transmission though. If you meant replacing the transfer case output shaft that darn near requires rebuilding the transfer case which isn't really that difficult or expensive, but it is a bit time consuming. Zumbrota sells rebuilt transfer cases for something like $2k, the rebuild kit is about $130 shipped from RockAuto.

Also, the shaft for the transfer case was removed when I had to get my flywheel replaced. The transfer case was already broken so they left it out

So I think we're confused. You have a 4WD Expedition and thus you have a transfer case, it can't be left out unless you replace the transmission tail shaft housing with a 2WD tailshaft housing.

I suggest you grab a helper to start the engine, shift into gear and such and get under the truck and see if you have driveshafts turning, if the they can be turned by hand it's gonna have to start with a physical inspection.

 

[Speed 330]

First thought is since you're seeing a speed indication tells me the transmission output shaft is turning. You'll want a helper or remote camera to see if the driveshaft is spinning while you shift through Park, Neutral and Drive. I'd look closely at the driveline from the point where the driveshaft couples to the transmission (is it 4WD? Then the transfer case becomes a variable...) to the differential and both rear axle shafts. Being push-able in Park tells me the driveshaft is no longer connected, so to speak, to the rear axle shafts, assuming the Park system in the transmission is working correctly. An axle shaft that has let go or failed (it's happened to me in a VW) will render you stationary with similar symptoms. Of course, and maybe most likely considering your symptoms, the differential itself could have failed internally. The grinding noise when attempting Park can be explained by the output shaft spinning and the parking pawl skipping over the indents in the parking gear attached to the output shaft. If there's no rotational resistance in the driveline the output shaft should still want to turn anyway while not in gear.

06 Eddie Bauer mine did the same thing the Sun Drum broke they're weak had my rebuilt Best Transmission I ever seen now