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2003 dodge 2500 HO cummins
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86 Posts
Discussion Starter · #1 ·
hey guys, started a thread the other week that didnt get any traction so ill try again

custom built trans and new triple disk with under 5000km on it.
since day one had the 1 to 2 shift hunt and hard shifts after.
truck shifts great for the first 5 minutes of driving but once i hit slow traffic and it hunts the second shift once all the others hit hard.
sometimes get a clunk at a downshift if coasting into a corner or slowing down after being on throttle.
other symptoms are going into reverse/ drive noticeably hard and with a clunk

did a band adjustment at 1000km didnt help.
did the bd upgraded solenoid and transducer also didnt help.
going to try band adjustment again cause maybe i was out of spec on the last one.
otherwise at a bit of a loss on what it could be, trans builder is leaning towards something with the truck/ecm or pcm and im hoping thats not it.

thanks for the read and any ideas let me know cause im about to launch it off a cliff. 馃が
 

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Ok, no expert, but I can maybe help a bit.

I have a 2003 also, and it doesn't use the ECM/PCM to shift. There is a separate transmission control module (TCM) on the firewall. It does communicate with the ECM, but controls the trans separately. It is very simple in what it does. From what I've read, it controls the governor solenoid (Trans pressure) based on the engine load, and decides when to lock up the TCC, and the overdrive clutch. That's it. All the shift points etc are done in the valve body, given a certain governor pressure. As many have mentioned, it's not a fully electronically controlled trans.

If you have done the governor solenoid and the pressure sensor, AND you have checked all the pressures as described in the manual, I suspect you have a valve body issue of some type.

Chay
 

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2003 dodge 2500 HO cummins
Joined
86 Posts
Discussion Starter · #3 ·
Ok, no expert, but I can maybe help a bit.

I have a 2003 also, and it doesn't use the ECM/PCM to shift. There is a separate transmission control module (TCM) on the firewall. It does communicate with the ECM, but controls the trans separately. It is very simple in what it does. From what I've read, it controls the governor solenoid (Trans pressure) based on the engine load, and decides when to lock up the TCC, and the overdrive clutch. That's it. All the shift points etc are done in the valve body, given a certain governor pressure. As many have mentioned, it's not a fully electronically controlled trans.

If you have done the governor solenoid and the pressure sensor, AND you have checked all the pressures as described in the manual, I suspect you have a valve body issue of some type.

Chay
ecm on the block, pcm on the firewall yes.
thats where im thinking the issue is as im running a brand new suncoast valve body ( still under 5000) so hopefully its not an issue in the trans lol
 

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Hope will only take you so far lol.

Typically the term PCM is powertrain control module and describes a device which controls the engine and transmission like the 2005+. You have a TCM, but semantics aside, it's very unlikely to be the TCM. It will work or not work, but won't partially fail.

It could be what it controls though, the TCC and OD solenoids or passage blockages etc...This is why you check the pressures.



Thinking about it, you could have an issue with the speed sensor on the OD though. I had an issue once and it caused weird stuff to occur. Shot in the dark, but worth a look.


Seriously though, report the pressures or you're just wasting your time here. No one can guess what's going on without more info.

Chay
 

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2003 dodge 2500 HO cummins
Joined
86 Posts
Discussion Starter · #5 ·
Hope will only take you so far lol.

Typically the term PCM is powertrain control module and describes a device which controls the engine and transmission like the 2005+. You have a TCM, but semantics aside, it's very unlikely to be the TCM. It will work or not work, but won't partially fail.

It could be what it controls though, the TCC and OD solenoids or passage blockages etc...This is why you check the pressures.



Thinking about it, you could have an issue with the speed sensor on the OD though. I had an issue once and it caused weird stuff to occur. Shot in the dark, but worth a look.


Seriously though, report the pressures or you're just wasting your time here. No one can guess what's going on without more info.

Chay
yea ill check pressures this weekend and report back,
reason im leaning towards electrical/ computer related is ive had other ecm/computer related issues in the past. some of them trans related
( had the pop in and out lockup problem and after checking cleaning and replacing everything i could think of a re flash on my smarty fixed it, after dodge told me they couldnt communicate so couldnt re flash)
anyways tho, this weekend im going to do another band adjustment and check pressures so ill update then.
thanks for the insight tho
hows a guy go about checking the speed sensor on the OD?
 

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I'm no auto trans expert but it sounds like a valve body setup/incompatibility issue...Did the builder offer (or is it still under warranty...) a warranty and/or honoring it?
 

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It sounds like this guy missed the setup in the valve body by a mile. What mods did he do in there? How is the TV cable setup? Where is your WOT 1-2 shift occurring?
 
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