Chrysler Repair: 1990 Chrysler Fifth Avenue Transmission, torque converter, tranmissions

Question
Hi Roland,
I've looked through many questions to try and find a specific answer that I am having with my 90 Chrysler Fifth Avenue New Yorker but haven't really found anything pertaining to me, that I can see.  My Fifth Avenue has been having some transmission problems and even more so in the past few days.
The transmission doesn't get stuck in any specific gear, however, accelerating from a stop there's often loud clunking noises until it seems the tranmissions "catches" itself and I can continue on. Also, when I am stopped I will feel my car "shudder" and when I try to accelerate I get no response from the engine all I get is a sort of jerking until I take my foot off the gas pedal and try again.  This has also happened coasting down the highway and going to accelerate again.  I've read some answers that I should maybe do a diagnostic test? This problem has only gotten worse within a few days.  Do I need a whole new transmission? Or should I do a diagnostic test and find the problems? Replace with a used transmission? Your response will be greatly appreciated.
Thank you very much!
Robyn

Answer
Hi Robyn,
There is clearly something quite wrong. But the noise and shuddering could indicate a problem with the torque converter coupling between the engine and the transmission rather than the internal parts of the transmission. Other than to localize the noise (if it were coming from the joint between the engine and trans that would point to the torque converter) and also have the fault codes readout from the trans memory I don't think you can know for sure which is at fault. But I would believe that doing the diagnostic work with the trans still installed is going to possibly help make certain that what work is done is the necessary repair rather than the wrong repair. So if you know of an independent (non-franchise) trans shop you could inquire if they have the 6-pin body "bus" plug (not the same as the 5-pin used for engine controller readout) for Chrysler trans readouts of that era AND the readout tool to actually communicate with the transmission controller, and also what it would cost for them to do the readout and listen/road test the unit. Unless they can assure you of their ability to read the trans controller memory I would have it diagnosed at a Chrysler dealer.
I would not go with a used transmission unless it was a rebuild by a reputable shop and had the same warranty as you can get by having yours rebuilt if needed. These trans are so challenging to repair/diagnose I would not spend any money on a used one from a junk yard. But take advantage of the diagnostic capability that they have built-in. It would be good to do that before you get stranded. The fact that it isn't going into limp-in mode suggests to me that it may 'only' be the torque converter. But that will still require removal but not tearing apart the entire unit, unless the code readout indicates that is required also.
Try and get the code numbers and names and what they interpret them to mean and what they might recommend doing in response. Then write back and tell me what you learned. You don't have to make a commitment to do the repair to get the diagnosis. They even might apply the cost of the diagnostics to the repair build (if you ask in advance). Then you might call around and get a second bid on the repair as well.
Roland