I have linked this to a previous post because it is the same sort of thing (hope this is the way to do it moderators?)
Anyway like the linked post says I have spent £2000 on a refurb for my box. The specialists were great even though I wasn't 100% happy.
After the refurb it has stopped the shuddering when accelerating in all gears but it still doesn't want to let go of the gear when slowing down. It is better than it was before the refurb but still I don't think it is right.
It has been re-mapped with a stage1 map and is so much better more power and smoother.
With the limited knowledge that I have gleaned so far am I presuming that the box tells the car what to do and when and the gearbox ECU tells the box what to do and when? My concern is that something may be wrong with the ECU (if something can go wrong with that) and that's why it doesn't drive as perfect as it should even after a complete refurb.
Can these things be tested or reset or re-programed?
If so can anyone lend some wisdom etc. to maybe achieve this.
The last resort is to go back to the auto specialists and take them up on the offer of another complete box replacement but need to make sure have covered all posts before I do this because if it is something else then the issue will still be there after and that wouldn't be good.
Hope someone can guide me on this before I give up and sell :-( which I really don't want to do and er-indoors would be fuming considering what I have spent on this car so far!!
Well they did a complete refurb so they took the box out changed all the seals, split the torque converter replaced seals and all the plates in the lockup clutches as these were burnt out. I don't think they took the valve body apart just cleaned it up etc. Replaced the oil filter and new oil as expected. I don't have an issue with them as they have been in the business 40+ years and dealt with a lot of Chryslers to the tune that the owner had a few 300's and recently got a Gen2.
I drive it in full auto mode i.e. normal driving.
When I say shudder its like you are coming up to a roundabout and the engine revs slowly go down but it feels like it wants to stay in that gear and not go to the next lower one, so if you were in a manual then not pushing the clutch in would give the same effect but not as severe as that. So the revs drop to below 1000 and it then lets go of the gear and the engine is free running if you get my drift but when it gets towards the 1000 and below it starts to vibrate/shudder.
So looking at what you say about the PCM and TCM if one of them is not doing its job can it affect the way the box acts?
So it's not "shifting down" as you decelerate. If the TCM is failing to send the proper signals to the PCM then that may be one cause but that sort of failure normally throws a code.
I doubt it will be the pcm, As i said in the other thread it is likely the Mechatronics board in the box that has failed,this board contains all the electronic circuits to control the valve block and is known to fail and i would think it would be replaced as a matter of course in a 2 grand rebuild, i would check if it has been changed. I think a check for codes would be helpful but you will need to try a garage that can read chrysler specific codes, most decent garages will have decent diagnostic kit. did the trans people actually carry out a diagnostic check or just offer to carry out a rebuild without the check for codes?
They didn't mention anything about replacing this board but while we were waiting for the owner to return from lunch we were looking at something on the bench and the other tech there said it was the Mechatronics from another car he was currently working on and said it was half mechanical and half electronic. He said it was the brains of the gearbox.
They never mentioned that it was replaced on ours and like you say maybe it should have been for a refurb of that cost. I will contact them on Tuesday and ask the question.
They checked for fault codes before and after the box was done as we saw the codes that were active which consisted of glow plugs (which are a recurring theme but not unusual I here) and the electric seat motors but nothing serious.
After I had it re-mapped I have noticed that the passenger window doesn't auto-close anymore and my seat doesn't go into exit mode (even though its enabled in the EVIC) I will be talking to the re-mappers on Tuesday too to see exactly how and what the re-map replaces/reconfigures the ECU or whatever.
Anyway back to the box I do so hope I can sort this as its fundamental to the nice drive that I would expect from this car and don't want to sell it.
Controls how and when to change gear. Which gear you need and monitors other vehicle sensors to ensure the gearbox performs as intended.
Valve-body (PCM)
A set of electrical and mechanical solenoids and sensors in the gearbox which control the engaging of gears and clutchpacks along with torque converter lockup.
For example;
You are travelling at 40mph in 4th gear and you let go of the accelerator to slow down. The TCM notices that the pedal position is at 0% and the speed is decreasing. In order to to keep the engine from stalling and to ensure you can accelerate if you needed to it sends a signal to the PCM to change from 4th to 3rd.
The PCM receives the signal and moves the necessary solenoids to disengage the clutch packs whilst deselecting 4th and selecting 3rd.
If you continue to slow down and come to a stop, the TCM then sends futher signals to the PCM to either select 2nd and then 1st etc... and the cycle continues.
If there is either a communication error from the TCM to PCM this could cause irratic shifting behaviour but more than likely it is the Valvebody to blame as it is slow on deselecting the gears (the mechanical process)
WOW that's what I was after thank you VERY much for that I will be asking questions on Tuesday to the Auto Box garage to see what they have and haven't done during the refurb.
I would have thought the same but wont know until Tuesday before I can answer the questions.
What is a conductor plate? and know about solenoids in the valve body and would have thought as a complete refurb would include all of this but have to wait and see what the answer is.
The conductor plate is similar to a printed circuit board in principle. It has contacts that the solenoids plug in to and where all the electronic signals are processed. It also contains speed sensors and the temperature sensor I believe.
So in theory then it could possibly be the TCM but that should give error codes which we haven't got so maybe its the conductor plate if that has speed sensors in it and I could see where it could go wrong when slowing down and not letting go of the current gear?
Just found this and sounds interesting as he mentions that if oil leaks into this plug it can cause issues with shudder and funny gear changes and doesn't throw error codes so will give all this info the garage tomorrow hopefully without them thinking that their Grandma knows how to suck eggs!! (think that's the right saying)
The plug adaptor or its o'rings should have been replaced as a matter of course with the Mechatronics/conductor plate if at all suspect as they are a common failure,
What can happen is oil can wick up the cable from the plug which is plugged into the mechatronics board and find its way into the tcm and cause problems but the tcm can be cleaned out rather than replaced.
However these are all things any auto trans expert/rebuilder should know and if it were me i would be well pi55ed off if my car was handed back after a 2 grand rebuild and common issues had not been attended to.... presumably they road tested the car and decided to hand it back even though it obviously still had faults.
However it could be as simple as a sticky valve in the valve block but this should have been checked and flushed out or replaced if there was obvious debris in the box from worn clutch plates as you mentioned.
Well been in touch with the garage and they did a bit more investigation and found that there are upgraded springs that can be fitted to the lockup clutch and stop my issue. I will ask them to check that plug at the same time if they havent already.
They are doing it FOC (of course) and will do it while we wait or go to breakfast etc.
Theya are also sending me a letter confirming that if they cannot resolve the issue then another box will be sourced/refurbished then fitted FOC again while we wait (well do a bit of shopping etc.)
So all in all apart from inconvenice the outcome should be happy.
Right another option has appeared. The garage has asked if I can get the TCM re-flashed as this could be causing the one issue that it has remaining.
Anyone any advice on weather this is worth doing as its a £108 charge by the Chrysler garage. I know there are no error codes for the gearbox at present so I presume that as this is the case the TCM doesn't have any issues.
Shall I do a fuse pull (from other posts) to see if this helps in anyway what do you think?
I have had exactly the same problem with my box for the last 3 years, the box only holds on to third and second on the overun. This only happens for the first 1/2 mile or so and only when cold. I have had the oil changed twice and it initially seem to cure the problem but it came back fairly quickly. I havn't done anymore than that because its only for the first mile (plus gearbox's = £000s). I did think of getting a second hand box off eBay as that costs a lot less and most give a warranty of sorts.
Its so annoying and once your tuned into it it's even more irritating.
I am sure it shouldn't do it full stop it should be nice and smooth.
As you can see what I have spent out and done to my box and its still doing it.
I will post when I have got the TCM flash or whatever the Chrysler dealer does and if it fixes the problem. I do know that the box before it went for the refurb was very worn but its disappointing to have it done and still have some issues.
Yes I agree with you about it being cold and mine is worse when cold but still does it when it is nice and toasty :-(
Well I am following this post with interest. As it only happens for the first mile or so it's not killing me but I have thought about a low mileage box off eBay. 2k for a rebuild which doesn't fix the problem is a nightmare I can not afford
Well the Chrysler dealer has done its stuff and they came back with everything is fine and all software versions are up to date and with no error codes on any of the control modules!!
Its getting worse when it cold its like de-accelerating over cattle grids now. :-( it does get better when warm but still doing it.
Anyway the gearbox garage has a valve body that they are re-furbing and also making modifications too for the lockup clutch issue so will have to wait now for this to go through and see what its like after.
Hope it sorts it and at least it gives me a starter for ten about where I start because mine can only get worse. Did you try changing the oil because I did and it made a difference but only for a couple of weeks. The gearbox guy was puzzled because he was saying that most problems are when the box is warm not cold. Where are you based?
As per my first post I didn't bother with just an oil change just had a complete re-furb (but not quite complete for whatever reasons presently)
When you say overrun do you mean when slowing down and the car trying to change down? If so from what knowledge I have gleamed so far is that your lockup-clutch seal may be warn which allows oil to bypass it and reduce the pressure on the clutch when it is supposed to release. Mine had shrunk to half its normal size.
Also all the clutch plates were also worn out too.
Been back to the garage today and they fitted the re-jigged/upgraded valve body. They added the stronger spring and enlarged the lockup valve thingy.
All seems ok nice smooth unnoticeable gear changes unless you watch the rev counter and no grumbling on slowdown so far but will wait a few days to make sure.
No charge as they said they would do whatever was needed to put things right and wouldn't stop until it is.
On a sadder note afterwards run down south.....::crying::
the issue has returned and as the valve body is OK it must be electronic but if it was that then it wouldn't go away and come back well I don't think so but then again the tcm tells the valve body what to don't maybe that's the next thing to be replaced.
Will contact the garage tomorrow to let them have the bad news.
I'm brain storming now to try and narrow down your options. The gearbox was fine when rebuilt and then the problems return after a few miles. A new valvebody was installed which was fine then the issue returned.
Now, I'm not 100% sure if the TCM resets after the battery is unplugged, if so, maybe the adaptions return to stock and after a little while learns bad habbits, suggesting the TCM is at fault or wiring.
I could be completely wrong and the new valvebody installed could be faulty or a sensor doesn't quite agree with the rest of the car.
Either way, I really hope you manage to get this issue resolved.
Just spoke to the garage and he said that the next stage to look at is the TCM and as you say could it be ok after a reset but then again go bad after a while....I don't know. He doesn't disconnect the battery as far as I am aware so are you talking about when the valve body is removed from the car and gets disconnected that way?
I will be talking to Chrysler this morning to ask about the TCM and how things can go wrong and what to do.
Before the valve body was replaced it was in the dealers for a complete check up on the TCM and all the other electronics and they said everything was fine no issues and all firmware's up to date etc. so at a loss at the moment.
UPDATE: forgot to add this due to wedding anniversary week (er-indoors gave me the look after seeing me on this site on the first day)
About 4 days ago and after the re-furb I was outside my garage and did a bit of work on the car (cosmetic) started the car to move it and put it in drive and then went to accelerate but NOTHING the car revved and didn't move. Wonderful I thought (amongst the panic) what's happened now, so switched the car off got out and locked it, unlocked it got back in and started it and it acted as normal. So it thought just a oddity but it happened again the next day same thing and to resolve it just switch it off and back on again and all was normal. It did it one more time but this time a gave it a god rev and it slammed into gear which surprised me but it was ok and sine then hasn't done it even after a trip down south.
Have you any update? I am still living with the problem but in the warm weather I am not getting much juddering and it's gone in half a mile. It does occasionally hold on to a gear ie4th when it should change down. Thinking of changing the box but if it's the PCM then that won't help
Well the update is that its still doing it, I think it is getting worse when it comes to the odd gear changes and also started to notice that sometimes there is a delay in movement and then a jolt as it engages. I have it booked into the dealers to have a recall on a part of the airbag system so while it is in I have asked to run it from cold and go for a 10-15 minute run (not the usual 100yds and back) to see the issue for themselves.
I am still thinking along the lines of sensors/TCM/PCM playing up etc. As the car has already been in and had a clean bill of health for all the relevant modules and as they are up to date then nothing to re-flash. I need to ask them if they re-flash the TCM/PCM how much and would it possibly cure the issues!
Mine is the same as it has been. Just occasionally when I am in 4th it seems to hold on for longer and doesn't change down quickly enough so judders. I will wait for your update but I have a feeling it is still mechanical not electrical
They have replaced my torque converter full stop and it has resolved all my issues so not sure what was wrong and was so fed up with it all I didn't bother asking but glad that everything is now ok.