5R55W - P0775 code

[Glacier991]

Neither does the pan.

 

[MRStace84]

Neither does the pan.

Are you saying that the pan doesn't have to be removed? It looks like when you pull the servo out that the O/D band will drop down. Can you give some detail about how to chance the servo without pulling the pan?

Thanks.

 

[Glacier991]

If you plan on using the servo cover compressor tool FORD makes, then yes, you will need to remove the pan as it bolts on the pan rail.

If not, and you can come up with some makeshift way to compres the cover enough to remove the snap ring then no, you might not need to pull the pan.

Inside the servo cover is the actual servo. It looks like the one in the pictures in the A4LD Rebuild Diary, just bigger. It presses into a band actuator than CAN fall when the servo is removed, but if done carefully most of the time will remain in position undisturbed.... allowing replacement and reengagement.

You are right, in that removing the pan will enable visual confirmation of this fact - I was not trying to say it's wrong to remove the pan... just that it can be successfully done without doing so.

 

[MRStace84]

Ok, well I do like the idea of maybe not having to pull the pan to do this job. One question. Is it easy to tell if the band actuator does fall? I would hate to put these thing back together and assume that everything is correct, and end up doing more damage by it not being togehter correctly.

I don't have the tool from ford to compress the spring, so I will have to come up a makeshift compression jig anyway.

BTW do you recommend droping the exhuast to gain access to the servo, or going donw throught the floorboard?

 

[Glacier991]

To be honest I have never replaced a servo with the tranny in the vehicle, so I'll defer to others. The CAT is a major headache either way though.

 

[MRStace84]

Ok, I am kind of at a cross road as what do try to do with this vehicle next. The problems with it are when it tries to upshift into 2nd or 5th gear. I have never had a problem with it downshifting.

I can turn Overdrive off, and when accelerating release the gas and it will shift into second. I drove the car for about 20 miles yesterday doing this and the O/D light never did start flashing or the PCM throw a code. However, if I keep accelerating, it will not shift into second, and around 30mph, the O/D light will start flashing.

Manual first gear does have holdback.

The solenoid pack has been replaced, and well as new fluid and filter. O/D band has been adjusted, so I know it is not broken.

It appears that is it a valve body problem, or the O/D servo is bad. Which one do you all think that it is? I am thinking if the O/D servo was bad that it would not go into 2nd gear at all?

If the valve body is the problem, what all should be replaced? the entire valve body and separator plate?

I am needing some advice and logic as to which of these is most likely the problem.

As a recap, the original symptoms of the car is that it will not upshift into 2nd or 5th gear. When the tranny fails to shift into these gears the PCM will have an error code of P0775, However, as I mentioned above, I have found that if I release the gas pedal at about 20mph the car will shift into second, and no error codes.

Thanks for all your help.

 

[Glacier991]

I think you are on the right track.... Looking at my 5R55W FORD manual, it lists P0775 as a functional fault of the pressure control solenoid.... but appears that the code may be set by some calculations (probably rpm and speeds) as opposed to a reading from the solenoid... which makes me think that there could be other issues causing it besides just a functional solenoid fault.

When you follow the diagnostic tests for that code, they are listed under pinpoint test D, which measures resistances in various parts of the VB and associated wiring. ALL of the tests either have you checking the solenoid block and replacing it (which you did) looking for functional faults in the wiring harness (internal and external), and checking the PCM. If all that fails, you are sent to the diagnosis by symptom chart, and it oddly does not list any mechanical or hydraulic issues, but rather lists just the PCM, wiring harnesses and solenoids.

I'm going to investigate the hydraulic circuits and see if I can possibly identify a spool that may be hanging up on the apply circuit for the OD servo. I'll post what I find.

It would be interesting to know your pressures, as I feel you have a pressure issue causing all this.

 

[Glacier991]

Well more research changes my thoughts here, and confuses me more.

I was incorrect, P0775 does check the voltage drop at shift solenoid B. This shift solenoid controls the intermediate band.... in the case of the shift into 2nd, it causes the band to release. P0775 will produce a low pressure, inhibiting the release it would seem. So the OD servo may not be the culprit.

The OD servo is switched on and off by the shift solenoid C... acting through the OD servo control valve (Bore 202) and as modulated for release control feel by the VFS2 Modulator control valve (Bore 214). Yet somehow I am backing away from the OD servo being the issue here.

The W has two taps for pressure.... one is main line pressure, located near the Digital Transmission Range sensor at the case shift linkage, and one for checking pressure control solenoid C, located on the opposite side of the transmission.

Frankly I am a little stumped. But now you know what I know, for whatever good that does you.

 

[MRStace84]

Ok, thanks for the info.

I have never considered a problem with the intermediate band. I was thinking it there was a problem with this band, there would be problems with more gears other than 2 and 5. Since 2 and 5 were the only gears affected, that seemed to point me to the O/D band.

Other than there being a problem with upshifting into 2 and 5, from a driveability standing everything else seems normal.

Does anyone understand why releasing the gas pedal would allow it to shift into 2nd?

 

[Glacier991]

The issue likely at play here is not the application of the intermediate band, but its release. In the old days, takingyour foot off the accelerator caused vacuum to spoike, and often a sluggish vacuum modulator could be made to work. Now days, more often than not that action will goad the PCM to shift to he next higher gear, jumping past a bad one. In the A4LD often a broken intermediate band will be reported as "it shifts if I let off the gas" when in actuality it is shifting into 3rd. I am not suggesting you have a bad intermediate band however...though you might try adjusting it and see if that helps.

I'm coming back to pulling your VB and rebuilding it. 5R55W's have been around long enough there ARE shift improvement kits for them... I have not installed one, but have one on order for the W sitting in my garage.

 

[MRStace84]

As far a rebuilding the Valve body, I am assuming that rebuild kits can be purchased for them? Should I look to get one from Ford or an aftermarket vendor? Could you suggest, what all I should get, and a recommended source from where I should get it?

Thanks again, for all your help.

 

[Glacier991]

Often the Shift correction kits contain parts outside the VB that can only be replaced during a rebuild. As I have not received my 5R55W kit yet, I cannot say how many parts will be useable in a VB only rebuild, as compared to a complete tear down. That said... the Transgo kit can be obtained here:

http://www.transmissionpartsusa.com/FORD_5R55W_S_N_SHIFT_KIT_2001_04_p/500-00023935a.htm

There is a Superior (that is a company name) Shift kit but it only has a pressure relief valve with O rings in it for the VB. You will need new gaskets from the FORD dealer.... and a 1/4 inch inch lb torque wrench. That site also has new servo pistons as well and a few other parts for the 5R55W... it is still new enough that the aftermarket is catching up.

 

[MRStace84]

Thanks for the info, Glacier..

Anyone else have any comments, that would like to add.

 

[MRStace84]

Well, I thought I would post an update. This evening I changed out the valve body, along with seperator plate with a bonded gasket. with a new one from Ford. Torqued everthing to spec, when I put it back together. The results is that is made absolutely no change at all. The car still has the exact same system that I describe earlier. While I was in there I did look, and both the overdrive and intermediate bands are intact.

So, unless it's the overdrive servo, I don't have a clue.

 

[Glacier991]

Well then we can narrow it down to a couple things. Either PCM inputs.... (not at all aware if there were any TSB's on reflashing the PCM).... or the servos or bands. In saying servos, there are two things to be aware of. The servos have a molded rubber sealing "head" if you will. That can harden or tear with a leak. The servo has two opposing lip seals, one for apply and one for release. They are a PITA to replace in vehicle. The servo rod can wear the bore it rides in causing a leak for release pressure. I am not really familiar with this, but I know there are aftermarket kits to address this (in the case of the 4R70W there is a servo rod with O rings on it to address this problem, for example.

At this juncture that is about all I can offer. Wish I was more help, I will add as I can. Re-reading this thread I come back to the "electrical fault"... that niggles at me...

You selling your otherwise good VB ?

 

[MRStace84]

Actually I've got to send the old one back to Ford for a core. Seems that all the dealers I spoke with had the core charge. They said the one I got was new and not reman, but they still wanted the core.

I'm hestiant on trying to change the servo's. When I had the pan off last night I noticed that I couldn't see the the servo side of the bands, but I could see the adjusment side. The concern would be that if the connector on the band drops down when the servo is pulled out, I don't know how one could get to it to make sure it's positioned correctly.

 

[stephiemarie]

Hi, I was reading the problems that you had, and was wondering if you could help me a bit. I recently bought a 2003 Explorer 4x4 XLT and have been having transmission issues (shifting hard, excellerating rpms). I used my scan tool and came up with 3 codes. PO732 Incorrect Gear 2 Ratio, PO735 Incorrect Gear 5 Ratio, and PO775 Pressure Control Solenoid B, I have taken it in to get estimates on it, and I know that it's the Solenoid, but since I'm a girl they keep giving me lists and lists of things wrong, when I checked it out, before and after they did, does this still sound like the problem? I cannot fix it myself, because I don't have all the tools I need.

 

[swetrid]

Hi, I was reading the problems that you had, and was wondering if you could help me a bit. I recently bought a 2003 Explorer 4x4 XLT and have been having transmission issues (shifting hard, excellerating rpms). I used my scan tool and came up with 3 codes. PO732 Incorrect Gear 2 Ratio, PO735 Incorrect Gear 5 Ratio, and PO775 Pressure Control Solenoid B, I have taken it in to get estimates on it, and I know that it's the Solenoid, but since I'm a girl they keep giving me lists and lists of things wrong, when I checked it out, before and after they did, does this still sound like the problem? I cannot fix it myself, because I don't have all the tools I need.

It is not the solenoid pack, the band or servo piston is broken. On 5R55W transmission 99% of time it is the band, on 5R55S 99% of time it is the servo piston. It sets the p0775 because the pressure goes out of the range because it cant apply band properly.

 

[kcwebguy]

...It is not the solenoid pack, the band or servo piston is broken. On 5R55W transmission 99% of time it is the band...

So what exactly is the recommended repair in this scenario? Remove transmission and replace? Or something more simple?

The shops says that their experience is that I have a pending total failure on my hands.

As add'l info, I am getting codes:

P0735
P0775

...and my fluid is dark according to the repair shop. The shop also says that a fluid and filter change will do no good at this point. Thoughts?

 

[maincran]

Ok, I am kind of at a cross road as what do try to do with this vehicle next. The problems with it are when it tries to upshift into 2nd or 5th gear. I have never had a problem with it downshifting.

I can turn Overdrive off, and when accelerating release the gas and it will shift into second. I drove the car for about 20 miles yesterday doing this and the O/D light never did start flashing or the PCM throw a code. However, if I keep accelerating, it will not shift into second, and around 30mph, the O/D light will start flashing.

Manual first gear does have holdback.

The solenoid pack has been replaced, and well as new fluid and filter. O/D band has been adjusted, so I know it is not broken.

It appears that is it a valve body problem, or the O/D servo is bad. Which one do you all think that it is? I am thinking if the O/D servo was bad that it would not go into 2nd gear at all?

If the valve body is the problem, what all should be replaced? the entire valve body and separator plate?

I am needing some advice and logic as to which of these is most likely the problem.

As a recap, the original symptoms of the car is that it will not upshift into 2nd or 5th gear. When the tranny fails to shift into these gears the PCM will have an error code of P0775, However, as I mentioned above, I have found that if I release the gas pedal at about 20mph the car will shift into second, and no error codes.

Thanks for all your help.

I am having the EXACT same problem with my 2002 Ford Explorer XLT. We bought it a about a month and a half ago. They guy we bought it from said the transmission had just been rebuilt and had less than 1500 miles on. A week later, it starts to go out. We drove it for a few weeks and it went down hill fast. I was not happy camper about this, but the guy we bought the car from had just moved from six states over. Instead of taking it all the way back to his home state for the warranty, I decided to just rebuild it myself.

I bought a rebuild kit, rebuilt it last weekend, everything was great for about a day and a half. Now, it is doing the exact same thing as MRStace84's post is saying. I got the same code tonight, and the exact same thing happens. The only way to get it to shift is to let off the gas.

I'm so annoyed with this transmission issue with this thing. I love this Explorer, but I can't seem to figure out where to look. I see everyone saying the Solenoid or the OD servo. I honestly just don't know which way to go with this. Was wondering if anyone found the solution yet?

Love the forums BTW. It was a huge help when rebuilding my tranny.