Chrysler Repair: Transmission Problem: Codes 0740, 1787, competent mechanic, pt water

Question
QUESTION: I have a 96 chrys. T/C I am on my fourth transmission, the van has 248000 miles on it. I had a compression test done and they said one side was 140,135,130 and the other side is 140,135,135. Can you tell me if this van is worth putting a another transmission in it? Also I have a 2002 Chrys.pt crusier the water pump needs to be changed. they are telling me it will cost a 1,000.00 to change this is this correct?

ANSWER: Hi Earl,
Those compression readings are good, relative to one another (spec is +/- 25%), and in absolute value they also meet the minimum spec which is 100 psi. On that basis I believe you have good rings and valves to warrant another transmission.
On the pt water pump, the amount of disassembly to get to the water pump and change it is significant whether you have the 2.0 or the 2.4L engine. It is about 25 steps in each direction to change the pump. If you have more than 75,000 miles on the engine it would be good to change the timning belt at the same time as it has to be removed in the process of changing the pump. You could do well to shop around for the best price you can get from a competent mechanic however. It is a job which the person should be experienced in and have the shop manual in order to do it right. I can't conjecture on what other prices you may find for the job.
Roland

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QUESTION: this is a follow up question my 96 Chrys. T/C van. The codes in the computer are po740,p177,p1787. Can you tell me what these are? I stopped at a stop sign, when I accelerated the van would not move. you could not push the van in neutral. 2 days later you could push the van but it was very hard. Thanks for your help.

Answer
Hi Earl,
The reason for the vehicle being hard to move is revealed by 0740 which says that the mechanical lock-up of the torque converter, which normally happens at speeds over 40 mph and should drop out when you slow down below that speed, did not unlock as it should have and the 1787 says there is either an electical or pressure switch malfunction in the part of the transmission called the solenoid/pressure switch pack which can be serviced/replaced without removing the transmission. It also can happen if the fluid level in the trans is too low or too high so check the dipstick. It is possible to be caused by a problem internal to the transmission which could require removal and repair. I believe the P177 is a typographic error, so let me know.
You might get away with a solenoid pack repair/relacement but diagnosis by a competent/independent non-franchise repair shop would be worth getting before you decide one way or the other. The lock-up problem might also be related to the solenoid/pressure switch assembly as well, so there is a possible repair which would be done without removal and rebuild.
Roland