I have read every thread on this forum regarding P0700 codes and still have a couple of questions.

GCS Specs: 2002 (Oct/Nov) Dodge Grand Caravan Sport; 125K; never an ounce of trouble from the tranny.

This morning my wife was driving the van and said she noticed a subtle shudder while cruising on the highway, but it only occurred once. A little while later she and my son both say there was a more noticeable shudder followed by consistent shaking. She immediately got off the road, put the van in park and waited and all was well - no more shuddering and shaking. Once she put it back in gear the shuddering returned and she was unable to go more than 10 miles per hour. Realizing she shouldn't continue to drive it, she pulled it off the road and called me.

Unfortunately I was MANY miles away working on swapping the springs on a boat trailer. I had her do the key trick and it came up with code P0700 (in addition to other unrelated codes that I knew about and was addressing). After finding out what the vagueness of the P0700 code meant, I had my son disconnect the negative battery cable, wait 30 minutes, reconnect and try again. The both said it "sounded" better when they started it, but after putting it in gear, same thing - shuddering and shaking.

After getting home a short time ago I talked to her at length as the van is many miles away awaiting tow first thing in the morning, so I have not inspected it. Her and my son both describe the feeling as a "shuddering/shaking" coupled with not wanting to get up and go. No grinding noises reported, but they both said they could hear a low regular "thump-thump-thump", primarily when in "Drive" and at first start up, but not in 3rd or low. No reports of burning smells. I felled to ask them to look under the vehicle for leaks, so I am vague there.

In the morning it is getting towed to a local shop for a diagnostic. I am just trying to get an idea of most probable issues so I am prepared to deal with the shop. I tend to do my own auto work, have all the necessary tools and a book, so I am hoping it's not the actual transmission - especially since I have had no real issues with the tranny other than a very occassional firm downshift when coming to a stop.

 

Just an update.

Got the car into the shop. Hopefully will hear something soon. I got a chance to check it out before the tow truck showed up. Will shift into Drive, but do not hear or feel a shift into reverse, third or low. In fact, reverse does not work at all. I did here a noise I cannot describe when driving it for about fifty feet - all I can say is it did not sound like grinding or loose metal but was definitely enough to make me stop. Other than that, fluid was at appropriate level, looked fine and didn't smell. No leaks either.

 

I'm in the middle of a similar issue. You can see my post just above yours on the forum list regarding the P0700 and P1776 codes. Although your issue seems a little more serious than mine at the present time, some of the things I've looked at on mine may cause your problem as well. I'm assuming the transmission controls are similar, but we likely have different transmissions, since mine is regular (not a Grand) Caravan. I have two speed sensors on the front of the tranny. (some only have one). The Transmisson control module (TCM) is on the passenger side of the engine compartment. There's also a solenoid pack just under the input speed sensor on the front of the tranny. The solenoid pack seems to be a common failure point...or a faulty speed sensor sending bad signals to the solenoid pack (via the TCM). The connector for the solenoid pack is oriented up...acting like a bowl for any fluid leak to collect in. The tranny cooler lines run just above the connector. If they leak, it will fill up the "bowl".

Just some things to look at...hope it helps. I haven't fixed my issue yet either. Let us know what you find out from the shop.