2000 Explorer Sport 4.0 SOHC 5R55E Won't Upshift

[MostlyNewExplorer]

The vehicle in the title. 5R55E Transmission. First I had the OD light blinking every now and then(for a long time) then the trans started to slip a little when I first put it in gear in the mornings, but was fine once I got going, so I added a little ATF, and all was well, then it started again, and eventually it started slipping more. The last day I drove it, the trans started to slip really bad, so I gave it a lot of pedal and it kicked into gear, but it wouldn't go into all 5 gears, it would shift from 1st to 2nd to 3rd just fine, but wouldn't upshift any further.

To make a long story short, I replaced the transmission with another 5R55e, now it won't upshift out of 1st gear while in Drive. So I'm running high rpms, but it's not upshifting. If I let off the gas and get back on the gas the trans slips and I have to rev the engine a little to get it to engage.

Could this be the shift cable out of adjustment? Or is it possibly a solenoid issue? Or something else?

This is a 4x4 BTW

Thanks in advance for any help.

 

[MostlyNewExplorer]

O.K. so I plugged a Code Reader(actron CP9125) into the diog. terminal, and got the following codes.

1. P0118 Temp Sensor(I broke it replacing T. Stat housing) I know what that is, not the problem(I don't think).
2. P0715 Turbine Shaft Sensor(TSS)
3. P0743 Torque Converter Clutch Solenoid(TCCS) I think it's the one at the back of the trans up near top, also part of harness.
4. P0750 Shift Solenoid Circuit 1 also part of harness.
5. P0755 Shift Solenoid Circuit 2 again part of harness.
6. P0760 Shift Solenoid Circuit 3 also connected to harness.
7. P0765 Shift Solenoid Circuit 4 you guessed it, connected to harness.

At this point I'm thinking that I may have installed the wiring harness upside down. I'll switch around the two connectors at the back(since they're easy to get to), if that clears some problems I'll flip the entire harness over and test again.

If problem still exists I'll check the Trans Range Sensor for a mechanical failure of the shift mechanism. Adjusted the cable, now I can put it into 2nd with shift lever, but still no upshifting.

After clearing the codes the check engine light went off and stayed off, but the OD light still flashes.

 

[MostlyNewExplorer]

I replaced the ECT Engine Coolant Temperature Sensor, and that cleared the P0118 and P0715 codes.

I still have these 5 codes.

P0743 Torque Converter Clutch Solenoid
P0750 Shift Solenoid Circuit 1
P0755 Shift Solenoid Circuit 2
P0760 Shift Solenoid Circuit 3
P0765 Shift Solenoid Circuit 4

Could just one sensor or wire/circuit cause a code for the rest to be thrown? If so, which is the most likely culprit? Thanks

 

[MostlyNewExplorer]

I did some more testing. Procedure as follows. Maybe this will shed a clue to someone as to what the problem might be.

First test
Erase Codes
Test Again
0 Codes(as expected)

Second Test
Erase Codes
Start Vehicle
Turn off vehicle
Test Again
4 Codes P0743 P0755 P0760 P0765

Third Test
Erase Codes
Start Vehicle
Move shift lever through all gears and back to Park
Turn off vehicle
Test Again
4 Codes same 4 as above

Fourth Test
Erase Codes
Start vehicle
Drive vehicle about 1/8 mile
Park vehicle
Test Again
6 Codes P0715 P0743 P0750 P0755 P0760 P0765

Vehicle still won't shift out of first gear while in Drive

 

[MostlyNewExplorer]

So, I got around to checking the wiring harness, and I noticed that the little metal clip that secures the 16 pin Case Connector plug wasn't installed correctly. So I left the clip off and just plugged the connector in the way it goes, test drove it and it shifted from 1st to 2nd, but flared between 2nd and 3rd, probably because the connector is loose. Then I tested again and got 0 Codes.

I can't for the life of me figure out how that little metal clip is supposed to go on there. Anyone know how that thing goes on?

 

[MostlyNewExplorer]

No Codes, then I took it for a test ride, flared between 2nd and 3rd wouldn't go into any gear higher than 2nd.

Now throwing P1740 Code. O.D. light is Not flashing.

Fixed a broken ground strap on the drivers side frame, now shows No Codes, but still won't shift into 3rd gear.

 

[MostlyNewExplorer]

I'm not sure how to proceed from here; does this trans need an O/D sprag or will a VB rebuild fix the problem?

 

[JK080]

This wont be a input sprag problem, it could be blown out valve body gaskets or a broken band or a internal failure of some kind.

I would pull the pan and inspect it for debris first, then if all looks good I would remove the valve body and inspect it for gasket issues and stuck valves. With the valve body off you can air check the servos to see if they apply the bands, also you may be able to see if the band is broken if you look up through the case openings when the pan is off.

 

[MostlyNewExplorer]

O.K. I'll do those checks and get back with what I find.

Thanks

 

[MostlyNewExplorer]

I was going to pull the pan today, but before I did I decided to take it for another test ride to see if anything had changed.

Sure enough, the Check Engine light came on, so I pulled the code. P1740 Torque Converter Clutch Solenoid.

I still have my old trans, so I'm going to pull the TCC out of it and put it in this one to see if there's a change before I do anything else. If that cures the problem, I'll still be putting in the VB upgrade.

 

[JK080]

The P1740 wont have anything to do with the 2-3 flare, or no 3rd or no 4th or no 5th.

Replacing the TCC solenoid may cure the P1740 code.

 

[MostlyNewExplorer]

So the 2-3 flare is either a blown VB gasket, a worn servo guide, or maybe one of the shift solenoids?

Also; do you know how the clip goes on the Case Connector plug? I was going to upload a pic of it, but when I click the link I get a popup add for Boiler Manuals.

So I posted it to FaceBook..

 

[JK080]

The 2-3 flare can be caused by:

Blown valve body gaskets
Bad 2nd solenoid ( the one next to the EPC )
Worn or damaged overdrive servo piston
Worn or burnt direct clutches
Worn valve body
Needs updated software in the PCM
Dirty MAF sensor
Crack in the center support bearing race


This transmission does not suffer from the worn servo bores like the later ones do.

 

[MostlyNewExplorer]

The 2-3 flare can be caused by:

Needs updated software in the PCM

A couple of weeks ago my radio started changing channels all by it's self, could that be an indication of this problem?

Worn or damaged overdrive servo piston

Do you mean the rubber piston inside the servo?

Dirty MAF sensor

I meant to clean that, thanks for reminding me.

This transmission does not suffer from the worn servo bores like the later ones do.

That's good to know.

 

[MostlyNewExplorer]

Cleaned the mass airflow sensor, no change. Pushed the Case Connector plug back into socket, fixed P1740 code.

Still can't figure out how this clip goes on.... This is the main connection for the harness that goes to all the internal sensors. I'm thinking the fact that it's not connected properly could be the problem, but I can't figure how this clip goes on. Anybody know?

 

[MostlyNewExplorer]

Pulled the pan on the 5r55e. Looks like this thing has been abused(off road), because the pan was pretty beat up, even had a small hole where it was creased, and I think I even found a little mud in there.

Found the usual carbon on the magnet, and this chunk of metal. The valve body gasket was blown, but needless to say I didn't pull the valve body. Also found a few needle bearings on the magnet, they're about 1/4 inch long and maybe 1/32 in dia, and probably due to "Crack in the center support bearing race" as JK080 mentioned earlier. So something going on other than a blown vb gasket.

The needle bearings. Probably due to "Crack in the center support bearing race".

Fluid comparison. Fluid on the Right is fresh. Fluid on the Left is new fluid that's been run through the trans. the past few days of testing.

 

[MostlyNewExplorer]

Update: Pulled the replacement transmission back out, along with everything else that has to come out first, AGAIN!

Took replacement back, got replacement for replacement, installed replacement for replacement along with everything else that has to be reinstalled, AGAIN!

WORKS PERFECTLY!

This time I pulled the pan on the replacement for the replacement, it looked good, no metal and not much carbon, fluid was a little dark, but not too bad, valve body gasket was in great shape.

Also replaced the pinion seal, on the rear differential, while I was at.