Trannies can be tempermental little B!t@#es

This could also be titled: Reason #237 Of Why I Hate Explorers...There are FOUR versions of this tranny!! 5R55N/W/S/E. C'mon Ford!

2004 Ford Explorer 4.6L 4WD with 5R55S. Came in needing a tranny. We opted to replace it with an exchange trans from our wholesale rebuilder. When done installing we could not get the transmission range sensor to line up. It would allow a start when in reverse. We've had this problem before but it's quite rare. I think the last one was 5 years ago and many, many trannies ago. We even tried ordering a new aftermarket range sensor but same thing. We had to grind out the holes to allow for that little extra adjustment. We ended up putting the new aftermarket sensor in.

A month later we get a call from the guy. The transmission works great. Shifts like a dream. The only problem is he has no manual third. It just goes into second. Boss-Man is very mechanical and hands on so he thinks right away that they messed up on the internal shifter linkage so he gets them to send a new rooster comb, manual shift valve, linkage rod and a few other goodies. It wouldn't be the first time a rebuilt unit had an issue.

So the vehicle comes in. Initial thoughts are the rooster is fine. When I move the shift lever it's not physically missing any of the detents and each detent perfectly matches the display in the dash. This guy is a PRND321. When I hook up the Verus and watch the Gear PID KOEO as I shift through the gears I get P-R-N-D-Man2-Man1-Man1. Immediately I start thinking range sensor. There are no codes and otherwise the transmission works excellently.

Boss-Man wants to look at internals. He remembers how much of a pain we had lining up the range switch initially. So I pull it in and drop the pan so we can compare roosters. Low and behold they are totally different!

Picture of both detent levers

Cue the celebrations and "I told you" from Boss-Man. The replacement one they shipped us had one less detent than the one installed. But wait a minute... That doesn't make sense. I can physically move it through each gear. If we installed a detent lever with one less notch then I wouldn't be able to hit manual 1st...

Here's where I start getting an indication of how much of a headache this thing is going to be... We call the dealer with all the part numbers and start figuring out what's supposed to be in here. The detent lever installed in the tranny is correct. The detent lever our wholesaler sent us is incorrect. It's out of a 5R55E out of an Explorer Sport Trac. Our transmission is a 5R55S. The Sport Trac just has a PRND21 and the regular Explorer has a PRND321. At this point I hadn't yet realized that the Sport Trac did not have a manual 3rd.

Boss-Man still totally thinks it's a mechanical issue. He's used to the older trannies where when you select manual gears it bypasses all the electrical and everything's applied hydraulically purely by the manual shift valve. But it was a slow day and he had to run on some errands so he let me have at it. Just make sure it's ready to go at the end of the day. The internals looked alright and we didn't have time to rip apart the valve body so I decided to go after the range switch. Do whatever I could to try and get the scanner to say Man3. After all... it makes sense. If the range sensor thinks you're calling for 2nd when you select 3rd then it's going to tell the tranny to go into 2nd. The pointer in the instrument cluster is purely a mechanical device and there's no sensor on the shift lever itself so the vehicle has no idea there's a problem and happily gives you 2nd thinking it's a good boy.

So I pull the sensor off the transmission and manually move it in my hand without any kind of linkage attached to it. No matter what I do I cannot get the Verus to say Man3. I get a little nervous when I graph the PID as the vertical axis does not have a Man3 label. It just has P/N - Rev - O/D - Man2 - Man1. I think there was another label at the bottom that either said "???" or "----". This makes me nervous because it wouldn't be the first time a scanner misinterpreted a signal. Holy hell that'll throw you for a loop if you're not prepared for it!!

Now, when we did the tranny swap we opted to put the aftermarket range sensor in. Fast forward to today and I got hopeful that the original sensor was still lying around but it must have been thrown out as I couldn't find it. Keep in mind, I have no idea if manual 3rd ever worked. So I got Boss-Man to order another aftermarket sensor. Again, in my hand manually moving it I couldn't get the scantool to say Man3. I then installed it into the vehicle and same thing. It was weird that I was able to get the aftermarket sensor to lineup without grinding it. Before we couldn't get either the original or the new aftermarket sensor to line up so we had to grind one. This one that I got was the same part from the same supplier as the one before so I would have thought I wouldn't be able to get it to lineup...? Weird, but it's still not saying Man3 so sideline that thought.

At this point I start looking at wiring diagrams so I can backprobe it. Check to see what's ACTUALLY coming out of the range sensor and what kind of interactions it has before it gets to my scantool. Here's where the headache really comes in and where I start throwing obscenities at Ford Motor Company!!! How are you supposed to diagnose things if you can't get good information!!! I checked Mitchell, Alldata and Identifix and none of their wiring diagrams showed a range sensor with a contact for manual 3rd!!! The only one that did was an ATSG book but it was for the older tranny that used slightly different colors that went to slightly different pins on the ECU. The good news is all the pertinent gear sensor wires go directly to the ECU. The only thing inside the transmission is a solenoid pack and it does not interact directly with the range sensor. Different harness all together.

This range sensor has 7 internal switches but there are only 4 that I care about. TR1, TR2, TR3A and TR4. So I backprobe each of these wires at the computer to see what I'm getting in each gear. This is with the new aftermarket sensor in. I didn't have time to compare it with the old aftermarket sensor. The results I got would match perfectly if the sensor was setup only for PRND21. None of the wiring diagrams that match this car list a 3rd position but each information source had a chart comparing the different switch states for each gear. That chart did list a manual 3rd and each chart for each source was the same so at least I could combine the two for something I feel fairly confident in.







The range sensor connector is the exact same for the Sport Trac. The switch chart is the same too except it doesn't list an entry for manual 3rd. All other gears switch the same. The Sport Trac wiring diagram shows the exact same colors, pins and internal structure as the regular Explorer for the range sensor. It just shows different pin locations on the ECU.





I'm thoroughly annoyed that my Verus only gave me a PID for the voltage on TR3A and a PID that said what gear I selected. The gear PID is processed data through. The only way you can verify that is you need to compare TR3A with TR1, TR2 and TR3. Why the heck don't I have PIDS for those?? Why do I have to manually check it myself?? My Snapon rep is going to get an earful the next time he comes around!

So I run out of time and have to throw it together. I put the old aftermarket sensor back in as the new one didn't make any difference. Recheck with the Verus and can't get a Man3 reading. I then hook up my little Autel scanner to confirm and same thing. No Man3. HOWEVER!!! MY FREAKIN $300 AUTEL SCANNER THAT I BOUGHT 7 YEARS AGO GAVE ME LIVE DATA FOR TR1, TR2 AND TR4 THAT MY EXPENSIVE SNAPON VERUS DOES NOT!!!!!! Oh man it was a good thing my rep wasn't there!! At this point it's well after hours, the customer is there and I have to let it go. Research time.

Tech Old-Timer was the one who did the transmission swap. He still can't get over the fact that he couldn't get the range sensor to line up. Keeps going off that it's the wrong tranny. Tell the rebuilder to ship a new one. But the tranny works perfectly for everything except manual 3rd... Again... if the tranny thinks you're selecting 2nd when you're at 3rd then you'll never get manual 3rd and it'll never think there's a problem. If that's the cause then you can replace the transmission and still have the same problem! There are huge consequences here... This transmission is UNPLEASANT to replace. Not to mention it's REALLY easy to have one minor mistake when rebuilding a transmission that throws everything out. Imagine if the replacement is a bad rebuild!! Imagine spending a day replacing the transmission only to find out that not only does it not fix the problem but the replacement has a problem and you have to spend another day putting the previous one back in and you're still back at the same issue! It's VERY easy to waste a ton of time here!

Boss-Man's still convinced it's mechanical. He calls up one of his buddies that's also in the transmission rebuilding business. He agrees that it should be mechanical and that hitting the manual gears bypasses electrical controls. So he pulls out one of his transmission repair manuals (ATSG). He goes to the component application chart and finds an Intermediate Band that only applies in manual 3rd. So he thinks there's an issue with that. That when you select 3rd it fails to apply that band and then slips into 2nd instead. How would it do that though? If the band fails then you're most likely going to have a neutral condition in manual 3rd. We don't have that. When you put it in 3rd it drives just fine except you get 2nd instead. If it were capable of realizing that it failed to apply that band then it would have to switch other components in order to apply 2nd. You would have a code for that. As well you should feel some kind of hiccup before you got 2nd. Not the case. Totally smooth when you select 3rd. And if that were the case you'd still get 2nd when you select 2nd. This vehicle gives you 1st when you select 2nd. If it tried giving you 3rd but then switched to 2nd you'd get: P-R-N-D-2-2-1. Not the case. This vehicle gives you P-R-N-D-2-1-1.

After Boss-Man left I noticed that the manual he grabbed was for the 5R55N. This vehicle is a 5R55S. I found a manual for the 5R55W/S. In the W and S models that band is also applied in third gear when you are driving in D. Everything works perfectly in D so that can't be an issue. We have to be left with some kind of control issue.

I then did some parts research. I went to the dealership but it was Saturday and they only had lube techs on so I couldn't get any service info but was able to get parts info. Including OE part numbers for the range sensor for the Explorer and Sport Tracs. They are different which makes sense. That switch state chart I attached is the same for the Explorer and the Sport Trac except the Explorer has an entry for manual 3rd. If they were the same part then how could they have the same switch state for Man2 when the Explorer has another gear physically in between D and Man2..? The only way that could happen is if the detent lever for the Sport Trac had an extended portion between those two detents. It would have to be able to physically move the range sensor further to get it to the same spot as the Explorer for Man2. But in the photo comparing the two I can see that's not the case.

The OE part for this Explorer is from 02-10 and 07-10 for the Sport Tracs but 02-06 Sport Tracs have a different part number even though the pin layout of the sensor is the same. At this point I looked to see what was ordered. That's when I noticed that the new one Boss-Man ordered for me was the exact same part as what was ordered previously. The suppliers interchange for this part listed both OE part numbers. I can't see one sensor working for two different shifters... So I think the problem is we're getting sensors for the Sport Trac. I think we're going to have to order a sensor from the dealer.

The only thing I can think of doing is to try manually supplying a signal for 3rd. The wiring diagram in the ATSG book I found does show a Man3 position inside the switch. The wire colors are slightly different than my vehicle and they go to different pins on the ECU but the internals of the switch appear to be the same. Just with the addition of contacts for Man3. So I should be able to unplug the sensor, jumper a few wires and then have the scantool read Man3...

But ya... everyone's ready to throw another tranny in this and I don't think that'll make any difference... :S

Dude, I love your tenacity here Everyone wants to throw parts, but you know it won't help! Also, THIS:

There are huge consequences here... This transmission is UNPLEASANT to replace. Not to mention it's REALLY easy to have one minor mistake when rebuilding a transmission that throws everything out. Imagine if the replacement is a bad rebuild!! Imagine spending a day replacing the transmission only to find out that not only does it not fix the problem but the replacement has a problem and you have to spend another day putting the previous one back in and you're still back at the same issue! It's VERY easy to waste a ton of time here!

TRUTH. Perfect explanation of why it's so important to know what the problem is before taking stuff apart. Especially stuff as complex as automatic transmissions :lol:

Seriously, I'm ASE A2 certified, and I have no idea what goes on inside them. It's all voodoo magic to me :blink:

I liked Explorers before they switched to that goofy set up... :pinch:

I checked out Alldata to see if they had a diagram that includes the range sensor, and haven't found one yet. Just a connector pin out.
This is the OEM part # they have listed for the sensor for that truck if it helps: 5L2Z7F293AA

The fact that with the sensor in your hand you can't get a man.3 conformation on the scan tool sure makes it sound like a faulty (incorrect) range sensor. Either that or the input isn't making back to the PCM.

And yeah, those transmissions are not fun. I'm good at them now, but they're far from my favorite. (I keep extra converter nuts around for those, and a couple of those fancy drain/fill/check plugs.... Jerks... )

Stick with it, I can't wait to see where this one ends up!

This one is disappointing....

Question: How do you know it's in second gear and not third when you select 3? I mean, how did the customer know there was an issue? I'm sure he didn't jump in with his Verus and run it through the gears on his way to work, right? lol!

3rd Position-3rd Gear
The third position provides:
third gear start and hold.
torque converter clutch apply and release.
improved traction on slippery roads.
engine braking.
2nd Position-2nd Gear
The 2nd position provides:
second gear start and hold.
torque converter clutch apply and release.
improved traction on slippery roads.
engine braking.
If this position is selected at normal road speeds, the transmission will downshift into the next lower gear, and continue downshifting until the vehicle reaches second gear.

Noah wrote: I checked out Alldata to see if they had a diagram that includes the range sensor, and haven't found one yet. Just a connector pin out.
This is the OEM part # they have listed for the sensor for that truck if it helps: 5L2Z7F293AA

Yeah, I really don't like Alldata for wiring diagrams. Much, much much prefer Mitchell. Though Alldata has way better re&re procedures. Usually has bettery theory of operation too. I actually got the OE part number already. That's where we're going to end up getting it is from the dealer.

Noah wrote: The fact that with the sensor in your hand you can't get a man.3 conformation on the scan tool sure makes it sound like a faulty (incorrect) range sensor. Either that or the input isn't making back to the PCM.

Circuit integrity is fine as I was backprobing right at the computer. The problem is going to be that it's the wrong sensor.

There's the regular Explorer then there's the Explorer Sport Trac. The regular Explorer had the 5R55S transmission from 2002-2010. It has manual 3rd.




The Sport Trac from 2002-2006 however had the 5R55E transmission. Almost identical tranny but it didn't have manual 3rd.




The range sensors for both are physically the same on the outside but internally the one for the Explorer has an extra contact in the middle for man3. Both put out the same signals for man2 and man1 but the Explorer has to move further to get to man2 so there is no way these could use the same part. As backed up by the fact that Ford has different part numbers for both.

The problem is with part suppliers. Man they can throw you for a loop like in this case. Our suppliers, as well as most I've seen online, are trying to say they both use the same sensor. Both suppliers have an interchange listing both OE Ford part numbers saying that their sensors work in both the Explorer and the Sport Trac. So they're going to be giving us a Sport Trac sensor. One designed for a PRND21 setup that physically does not have a contact for man3. Once everything's considered that becomes the only possibility that could explain everything this vehicle is doing. I won't see the vehicle again until next week.

Noah wrote: Question: How do you know it's in second gear and not third when you select 3? I mean, how did the customer know there was an issue? I'm sure he didn't jump in with his Verus and run it through the gears on his way to work, right? lol!

They live up a big, long hill. They know it's going into second gear when they try to downshift into man3 for the engine braking. Instead of a nice controlled downshift riding at 3,500RPM they're practically bouncing off the rev limiter. Nobody wants to get hit in the face with a con-rod :lol:

Looks like you got it pretty well nailed down. Just gotta wait for the right part to come in. Nice work all in all.

So vehicle came back and the no manual 3rd problem was caused by getting the wrong part from the parts store. The weird thing is that if I look at both of our main suppliers I have access to 3 or 4 sensors made by different aftermarket companies. Yet ALL of them list BOTH OE Ford part numbers in their interchanges... It's crazy that they would all list the wrong sensor. Physically they look identical and internally they are very similar. If a customer came in needing a replacement sensor and you replaced it you probably wouldn't realize it was the wrong part. P, R, N and D would all work perfectly. It would start only in P and N. It would feel totally fine. Most customers wouldn't even realize they had man2 instead of man3 for a long time.

Before I installed the new OE Ford sensor I manually checked it. For man3 it connects pins 3 and 4 to sensor ground (pin 2). Sure enough, I found a position for that. I then went to the vehicle, unplugged the sensor and jumpered all those wires together with backprobes. Sure enough my scantool read man3 for the data PID. At this point I knew it would work.

When I installed it I was back to the original problem of not being able to get it to fully line up. It was off by one gear through the full range. I had to grind the heck out of this sensor to get it to lineup. Way more than the previous one. Which makes sense because the previous one had one less gear selection. I managed to get it in and get everything to lineup. All gears perfectly lineup with the PRND321 display in the dash as well as the gear data PID on the scantool.

I think the problem with this tranny build is with the shift lever shaft. The shift cable connects to a small lever on the outside of the trans. That lever connects to a round shaft that goes through the range sensor and into the tranny. It's fastened to the shift detent lever which has a pin that moves the manual shift valve inside the valve body.



Not the best picture for demonstrating which part I'm talking about but it's the only one I have The shaft I'm talking about is the part I'm holding.


The only thing that makes sense is if that intermediate shaft in the shifter linkage is slightly different between these two versions of this transmission. That wouldn't affect the detents so you could still get it to match perfectly with the display in the cluster but it would throw off the range sensor a bit making it hard to line that up. This tranny was built by a wholesale rebuilder that probably builds a couple hundred trannies a month. When you're doing that many and you're going to have that many bins of hard parts it would be so easy to accidentally grab a small part for a 5R55E and put it in a 5R55S... Internally these trannies are so similar that they probably just have a bin marked 5R55N/W/S/E. :dry:

All in all we made it work. Good riddance to that thing!

Nice work! Stuck to your diagnosis and nailed it, that's what it's about.

Holy CRAP this was a trip :lol: Well done for sticking with it, sir.

I agree, I think this vehicle could have gone the rest of it's life and no one would have noticed the problem. The owner just happens to be the 1/100,000 drivers that actually use the manual gears. I feel this way a lot with alignment problems

How'd Boss-Man and Tech Old-Timer react to the fix?

Tyler wrote: I agree, I think this vehicle could have gone the rest of it's life and no one would have noticed the problem. The owner just happens to be the 1/100,000 drivers that actually use the manual gears.

Yup. Only reason why he noticed is he lives up a big hill and uses the manual 3rd for a downshift to get engine braking going down the hill. For a lot of people this wouldn't be a major issue. After all, everything else in the transmission works perfectly. But given his location and driving style the fact that this vehicle had a manual 3rd was probably a major factor in his decision to buy the vehicle. It's important to him and he paid for a rebuilt trans so it's gotta get fixed!

Tyler wrote: How'd Boss-Man and Tech Old-Timer react to the fix?

They reacted the same way they usually do. Boss-Man usually just shrugs or grunts and issues a "weird" or "that's dumb" and then goes back to doing what he was doing. Not trying to knock the guy but Boss-Man is very much a hands on, GO-GO-GO kinda guy. He's not good at thinking things through and figuring out consequences and implications. Deep critical thought is difficult for him. He likes simple things that he can see and touch. For something like this, at the end of the day, he sees you've changed a range sensor. Well that's an easy task... The thought process is: "If we had just done that all along we could have saved so much time!"

Say if you get a starter replacement job in something nasty like a Mercedes ML350 where it's completely burried and you have to remove 235252352 splash shields, covers, tin plates, brackets, etc... Then he'll throw praise at you. It's easy for him to see and understand how stupid that job is.


As far as Old-Timer goes then his reaction depends on what mode he's in. If you're on a difficult diagnosis then every time he walks by you he'll throw out a new possibility. "It's probably this...", "I'll bet that's the problem there...". So when you find the problem he's able to come by and say, "Ha! Ya, that's what I said." ... :S But you listed every freakin part in the whole car!!

The other mode is he gets fixated on an idea. He won't just beat that horse until it's dead but he'll keep beating on it until every future life of it is dead too!! So in this case he was fixated on the tranny. "The tranny is wrong! Get a new tranny!" He's technically correct but that's way too broad to be useful. If you're going to go through the effort of getting them to build a new trans then install it then you have to narrow down the actual problem so that you can have a degree of confidence that all that effort will fix the problem...

So Old-Timer reacted by, "Ha! If they built it right the first time we would have just used the original range sensor and never had any of these problems!" Well yes, that is correct, but that doesn't change the fact that we have to solve the problem at hand!


It can be hard to get proper appreciation. You're doing things they don't understand. That makes them feel a little dumber and lesser than you. They don't like that. They have way more experience than you. They don't like some kid coming around telling them they're wrong and acting like they know more than them. Now, of course I don't act like that. I respect their experience very much and try to be gentle as possible. But it's a perfectly natural human response. As long as you are many years their junior you will always run into resistance and skepticism. No matter the results you get.

But that's okay. I do it for my own ego. I consider myself pretty capable now but I've still got a solid 20 years left of active wrenching. So that's what gets me excited! Thinking about the level I'm going to be at after 10 or 20 more years of this! :lol:

ecwurban wrote: For something like this, at the end of the day, he sees you've changed a range sensor. Well that's an easy task... The thought process is: "If we had just done that all along we could have saved so much time!"

What's the saying? It's not the trip, it's the journey? Boss-Man sounds like the kind of guy that see that you went from A to B, not that you had to take a detour to C, side track to D, make a stop at E, backtrack to C, and finally get to B :lol:

But that's okay. I do it for my own ego. I consider myself pretty capable now but I've still got a solid 20 years left of active wrenching. So that's what gets me excited! Thinking about the level I'm going to be at after 10 or 20 more years of this! :lol:

Definitely capable! I honestly credit Paul for jump-starting my career in automotive diagnostics. I might have figured all this stuff out, but it would have taken SO much longer.