Chrysler Repair: 99 Grand Caravan Transmission Codes 36,53, solenoid pack, shaft seal

Question
Thanks for the Help Roland:

I have a 96 GC with a 3.8 and the A-604 transmission.  The Trans was changed by a dealer at about 40K, the van now had 147K on it.  The Trans is in the limp mode.  I changed the filter and flushed 3gal of mopar fluid through it.  The pan was clean, just fuzz on the mag.  I took it to a shop and they read the codes 36 and 53.  The volumes were in the 60's except for 3rd which was 162.  

I do lots of car work but have not been into auto transmissions, where do I go from here.  Thanks

Answer
Hi Larry,
I'm about in the same state of ignorance as you on these electronic transaxles. I read the manuals but have no direct experience. But it is clear that rebuilds are very expensive (around $2k) and that everyone who has one has been told that it is needed at one juncture or another.
According to the manuals, the 36 code coupled with a 53 means that there is some slippage in 3rd gear and that it is not due to electrical issues but might be hydraulic or internal mechanical (e.g. a clutch (UD or OD), or accumulator/input shaft or clutch or reaction shaft seal ring, or gear set, all of which sound to me like rebuild). On the other hand also listed as possibilities for the 53 code are: internal solenoid leak, valve body leakage, regulator valve sticking, sticking valve in solenoid pack (check pack and valve body), and faulty cooling system. It sounds like some of these are done without removing the trans and could be within your competence if you had the manual that shows how to deal with the solenoid pack and valve body if you are up for the challenge. I'm not sure whether a competent and ethical trans shop would do that sort of checking and at what price. Maybe you could find one that would do that work first with the understanding that if it didn't bear fruit they would be given the rebuild job. I have several Chrysler manuals from that era that show the steps in disassembling the solenoid pack/valve body and would xerox and postal mail those pages to you.
The clutch volume is out of line for 3rd which is consistent with the code 53, but whether it results from a worn clutch or an hydraulic control problem is an unknown, at least to me.
So that is about the best that I can offer. Let me know if you want the pages. The fact that it has gone 107k miles is consistent with the distance one would begin to expect worn internal parts in these units from what I have heard.
I would be pleased to know how you proceed with the issue and the results of the effort.
Good luck.
Roland