Rebuilt tranny, fail when hot, any idea??

Hi AF friends, well, i'm from Mexico city, so my english languaje will not be so good as i expected, but well, i'll try to do my best LOL.

Well, now, i'm just desesperated, why? because my dear windstar 2000 3.8l engine, ax4s tranny, have a tranny failure, an it has just being rebuilt.

All start in a long travel (or journey??? i dont now, its when you just take your van and drive it to a far destination)

i have to tell that we bought the windstar as used car.

well, continue: i was driving it and then overdrive light started to blink i said "ho... cr...p" that horrible light, nooooooo. then the van started to rev up and loss traction when was into overdrive (or 4th gear) and then normalize, so i turned off overdrive, and it was "normal" but the light was blinking.

when we arrived to the destination, it has no Reverse and has difficult in shifting from drive to 1st and from 1st to second, also it doesnt engage 4th.

when returning fron destination, it was worse, has vibrations and strange issues while driving, so well, finally we arrived, also de mercon V oil was very very black, that means burned disks.

here in mexico its very difficult and expensive to find a rebuilt tranny, and people that "rebuild" the trannys are not experts, are just people that have a litle experience, but not so much.

so well, i've decided to rebuild my own transmission, it was a very difficult job, the van has to be jacked up in metal towers, remove wheels, safely support the engine, remove the front axle completely with the direction column on it (i dont know the exactly term for it)

well, the finally was the tranny, then, with the tranny out i proceed to... how can i tell it unbolt anything that has bolts? well, i remove all parts and put it on safe place, also i put in in order.


when opening, i note very strange things, oil pung was destroyed, so it damage its round ring, and make much metal little pieces taht goes to all the tranny.

then, when opened more, i found that revers discs and direct clutch was metal with metal, so disks was just to the garbaje, also the OD band was just metal, so, to the garbaje, and the worse, was the planetary gearset was litle destroyed.

i have proceeded to replace all disks, metal and no metal disks, replace the planetary gearset, all the orings, whashers, well, simplifying it, i replace almost ALL the pieces except the drums and big metal pieces.


finally i put the tranny in place, torqued it and tested it jakked, also it worked perfect, then i raised it to the floor and it works perfectly for a while, beacuase then it get warm and it has NO reverse and NO 1st gear, no manual 1st gear and no "drive" 1st gear, so the procedure, is to put in manual " gear, go to 10 KM/H, aprox 6 mph, then put it into drive and follow, but if i have to go to 0 mph, and then start to drive away, i have to repaet the procedure, put it in 2 and then into drive.



Please, if someone has experienced somethig similar, please help me, im desesperated, its very frusttrating that it does that to me :´( i have inverted a lot of money rebuilding it, and this its very desesperating.


PD:I have scanned it and throws two codes:

-TR low signal, (i have replaced and now the reverse lights works all right, but the problem proceeds)

-OS spedd output sensor, low signal (i havent replace it, but i test it, i just unplugged it, and the failure is the same)


and well, the failure its just when it is hot.


Thanks. Greetings.

Hola,

cambiaste los solenoides?, he leido algunas veces que la tira de conectores que va a los solenoides se vuelve frágil y puede ocasionar algunos problemas especialmente con el motor caliente.

Cambiaste la turbina? Es posible que con todos los pedazos de metal se haya dañado.

Cuál sensor desconectaste? OSS situado en el lado del conductor o VSS situado sobre la transmisión detrás del múltiple de escape trasero. El VSS es más común que falle.

Escribí en ambos lenguajes para ti y los demás, si es necesario puedo traducir los mensajes para el resto, por favor trata de apegarte al inglés aunque no sea muy bueno en caso de que yo no pueda revisar el foro.

Saludos,

Oscar.

Hi,

Did you replace the solenoids? I've read that the bulkhead connector becomes brittle and can sometime cause problems, specially with higher temps.

Did you replace the torque converter? It's possible that it was damaged with all the metallic pieces.

Which sensor have you unplugged? OSS located at the driver's side or VSS located on the upper side of the transmission, behind the rear exhaust manifold. A failing VSS is a common problem.

I've wrote in both languages for you and the rest of users, I may also help with translations if necessary, please try to stick with english even if it's not that good as I might not be able to log in everyday.

Regards,

Oscar.

Hi, thank you for translating and answering.

responding to your questions.

i havent replace any selenoid, and well, in the aplicattion chart, the shift selenoid number 2 its common for P R N, 1 and 2 so maybe, when it fails in P,N or 2 its not evident because in P and N the van isnt moving, and the 2 gear it actually its engaged by other solenoid. i will try to check it out its impedance in hot to se what happens.


for the turbine, or torque converter, i haven‘t replace it because it was very expensive, and also it wasnt new, but i wash it with a degreaser solvent, then left it to dry and then put a litle amount of mercon V to remove the rest of solvent. well, it maybe result damaged because of the metal pieces, but i want to discard first the external pieces before raise down the tranny again.


and the last,the sensor it was exactly the OSS output speed sensor, but i havent remembered. the scanner indicate that sensor, but when unpluged it, the van makes the same problem.


other thing that i noted is that my windstar, especifically the ax4s tranny, doesnt have the common VSS sensor, instead of that it has a metal cover with a ford part number. also doesnt have a conector, but well, i have read that the vss whas replaced in the ax4s for the hall type oss, also when i unpluged the oss, the velocimeter operates normaly.

the person in the part suplier place told me that because the vss was a common problem, now the signal comes from the abs sensor on the driver side frontal wheel, im not sure of that.

well now at least i have an idea of what to check. thanks.

I seem to remember that the signal for the speedometer comes from the ABS sensors, however the VSS is still being considered to determine proper shifting; that sensor is more prone to failure rather than the OSS on the driver side of the transmission.

I made a thread in this forum regarding the replacement and my windstar is also a 2000 so the process will be the same.

Oscar.

One thing that you must do is to verify that you have fluid flow through the transmission fluid cooler that is located inside the radiator.

With all the little pieces that you mention throughout the transmission are likely to also have gotten into the transmission fluid cooler.
This can block the flow of fluid through the cooler, causing your transmission to overheat.

If the transmission fluid cooler inside the radiator is blocked, the repair is to replace the radiator, in other words, you cannot repair that part.
One could install a auxillary transmission fluid cooler in front of the radiator, but you will need to get a big one if you are using it to replace the one in the radiator.
In other words, you could connect the transmission fluid cooler lines to the auxillary cooler INSTEAD of the radiator.
If your vehicle has the factory installed auxillary transmission cooler, it will NOT be big enough to replace the in-radiator cooler.

Hi folks, thanks for your answering.

Well, respect to the VSS and OSS, i've seen that my tranny only has the upper side OSS, and that sensor is a "Hall Effect" sensor, its located in the center of the tranny.

The common VSS that other windstars have, mine doesn't have it, i've seen that the common VSS has a litle gear on it, mine, in the place of the VSS has only a metal cap.

But well, i suposse that if that sensor fails, the OD light should blink (and it doesnt do it more) and the shifting should be improperly form 1 to 2, from 2 to 3, and from 3 to 4, and that is not the case.

Well, i torqued to 9 LB/FT all the valve body, and well, now the failure is completely diferrent (i remember that the pump bolts were very untightened, i could remove it by hand)

Now the trany doesnt overheat to much, well, al least doesnt smell burny, also i checked the oil level and was below the "do not drive" hole, so i refilled it.

After all that, i have test it, nd the results were different.

-Reverse has very strong when cold, it engages very well, but when it starts to hot it becomes to loose strong, when its completely hot, now it engages properly, but for start to moving the van i have to rev up the engine to 2000 and the Reverse engages, it has more power than before the torqued.

-Independient if the tranny is hot or cold, when i move from P to R, form P to D, or from N to D, or N to R it feels like the tranny engages somthing, also the revs come down a little, but if you accelerate in D it doesnt move, and if yo rev uo to 2000-2500 it start to move, but vibrating and with very poor power.

I will follow your recomendations because it fails more wheen wot, and maybe its overheated without i know it, so i will check out the radiator, in my windstar it only gets cooled by the engine radiator, it has a very thin radiator, but that radiator its only connected to the steering column, so it only cool the power steering fluid.

But well now the failure its slightly different.


I also have a question, it is possible that the tranny needs to be settle, becuse now the failure its less notorius, but it stays.

Other question, if one of the solenoids fails, doesn you know the symptoms? i mean, what happens if the EPC solenoid fails, or if the SS2 (shift solenoid 2) fails. because i havent change any of the solenoids, i've left the OEM used solenoids.


Many thanks, at least i have more things to check. :grinyes:

You are well ahead of me in your understanding on the tranny's internals and function. I suspect the "rebuild" you had done earlier, by someone else, was not very good ... based on its early failure and the loose bolts that you found. I cannot suggest any repair path for you to follow.

I know you have already committed time and money to the tranny's repair ... with little good outcome. I wonder if the local Ford dealerships offer across-the-counter exchanges of tranmissions? I have exchanged my broken transmission with a Ford remanufactured transmission for less than $2000. Of course, this is in Georgia and was a few years ago. This replacement came complete with fluid and torque-converter. It now has over 150k trouble free miles on it. Except for shipping costs, you would think something similar would be available there.

Good luck!

hi, well, i continue the google search hehehe, because if i move something in the valve body and the problem has changed, something should be bad there.


i found the sonnax sure cure kit, thet includes a new redesigned reverse boost valve and boost sleeve valve, i remember that this valve was very difficult to remove but after the cleaning it enters very easily into the valve body, so i think that it maybe this valve its damaged and its leaking, and for that i dint have reverse,


other guilty valve its the foward valve, that also comes redesigned in the kit, and also i doesnt take much care on it when i removed it, but the symptoms ecuals, because it slips in first and have a delayed second engagement.


well that kit it should be the las thing i will try before moving it to the dealership, but the price its 100 usd if i remember, and in the tranny repair shop, they offer me a guaratied rebuild valve body by the same price with all the sensors, also i have to left the old one for being rebuild by they so this is the last thing i will try, because its the only non-expensive posibility to try.



i will update the post with the results, and i expect that it should be satisfactorius, please, wish me luck :rofl:

Greetings

oh, i dont know if the dealer ship accept the old tranny "in change" i will ask, because the orice they give me for a new one was aproximately 6000 dollars, its more that i have payed for all the van, but maybe in exchange it should be more cheaper.

oh, i dont know if the dealer ship accept the old tranny "in change" i will ask, because the orice they give me for a new one was aproximately 6000 dollars, its more that i have payed for all the van, but maybe in exchange it should be more cheaper.

That's insane! They must have really messing with you or must have been because of the area. Where I currently live (León, Gto.) they want $20,000 pesos ($1600 USD) for a new transmission already installed.

That's insane! They must have really messing with you or must have been because of the area. Where I currently live (León, Gto.) they want $20,000 pesos ($1600 USD) for a new transmission already installed.

of course its very insane, and the rebuilders wanted 20,000 MXN and they arent very reputable people so i started the rebuild process by myself, beleiveme that if i should received a cost of 1600USD i should asked for a discount becuads i shouldnt need the intallation, and also it should be very less problematic that all the things i am passing.


and well, now returning to the old windstar, i have changed all the valve body for a rebuilded one with new sensors and pumo.


the problem is now more strange i am thinking in a internal leak of oil, i dont know where, but ther are two posibilities, on the N-D acummulator or the intermedium band servo, also it could be a piston of the clutch packages, but i dont think so because there are all new.


i am almost sure that its a leak in the N-D servo because when it fails it provocate a hard shifting into reverse or low, the low makes the hard shifting in anyway, i mean if you select 1 or you select D it makes the hard shifting, at least that says wikipedia, and the logic makes me think that if that has a leak, the generated pressure should be inssuficient for applying that gears.


well i tested out in the highway, or freeway i dont know how is the correct translation, and well it feels very very well, the upshifts were so smootly almost unfeelables, also the downshits for accelerating, there were a little retarded but it was very well, so because the fixing needs to remove AGAIN all the tranny i will left it in that status untik the next vacations period.



many thanks to all for your helpfull


i will try to apport things to the windstar subforum.

The 20,000 MXN quote I'm talking about came from a Ford dealer, not a shop. I've been willing to pay for it but unfortunately money is tight and have had other health problems with a family member so the windstar has to wait...

I remember reading somewhere that an incorrectly positioned valve (on the side of the valve body) would cause a harsh shifting. The guy took it out and turned it 180º, reinstalled and tested and the problem was fixed.

Good luck with your minivan; hopefully that transmission will last.

Oscar.

Hi, how are you, sorry for don update the post, it was because i was slighly busy, but well, now i am a little more "free"

well, lets continue with the history. finally at the last chance before droping out the tranny again, i replaces a rebuild valve body, the result: the same, no reverse, no first, all the other was just right. so what was the problem, well, the inside.

but well, i needed the van and i just take it to travel to a relatively far distance (aprox 100 miles) and during all the travel the van do it very well (except for the problem of course) but when we were returning, form a moment to another, it started to drop the oil, and lot of smoke comes from down the van.

i inmediately stopped the van, and well, the oil was falling out from the space that is between the engine and the tranny, so, the failre could be a damaged converter seal, o a bad torqued bolt from that side of the trany.

so finally the van supported all the highway travel, but in the city it was no more oil for applying the clutches, and it was towed to home.

to the day of today, i have AGAIN the transaxle aout of the van, this time, i remove all the stuff in about a day (well, this time i know how does all things were removed, so it was very much faster) and i have open it again.


finally, i saw the problem, and if i should know it before i could save myself much money for the tow truck.

well, the problem was a bad assembled direct one way clutch, it was not making contact with one clutch disk, so it was more "outside" from it place, this causes, an excesive pressure over the low one way clutch, and to become overheated becuase it makes much friction with a plastic washer. So when i tried to separate the overdrive drum, it was very dificult, but finally i saw a plastic washer, completely melted because of the friction and well, that causes the one way clutch to doesnt turn free in the direction that it should turn free, specifically it was in first, and reverse so that was the cuase of the correctly function when first started, but after the first drive, it started to fail.


well AF friends, i will keep you informed, but by now i have just to buy a friction disks package(becuase it become damaged cause of the stucked one way clutch), two new plastic washers (because of the melting) and a new gasket kit for the rebuild. well also the 12 quarts of Mercon V but that is tha last thing.


PD:I have in my own varios manual about dissasembling and assembling the Axode and family transmission, apliccation charts, etc; this are in PDF formats and are from the ATSG and transtec, if you want it just send me a email or write a post requesting it, i can say that they were very usefull for much specifications (the problem was that i doesnt understood varios terms of the manuals because there are in english, but they are very useful.


Greetings and thanks for all your comments ;)

Congratulations on your find!