97 Grand Caravan - Overheating & transmission Codes

Looking for wisdom on a couple of 1997 Dodge Grand Caravan LE issues. The 3.8 Liter v-6 is rapidly approaching 100,000 miles and began overheating during long idles about a month ago. Thinking back to my 78 Nova days, I immediately put in a new thermostat. Needless to say that didn’t fix the problem or I wouldn’t be here.

About two weeks ago the van began overheating per the gauge, but no warning lights so I began driving it. Then it got stuck in 2nd gear. I took it to AutoZone to run the codes – P0700 and P1767 – both trans but nothing about overheating.

As weather got warmer, and Momma started calling with 2 kids in the car saying its overheating again, I took it to the dealership. I’m sure from reading the posts that no one would guess the answer of, “You need a rebuild on the trans $1600 to $1800”. And they didn’t check the overheating problem because the faulty trans is probably causing the van to overheat. (by the way their codes were 75, 47, 74 - trans overheating and debris in valve body).

Here is what I know of the van to date:

Up until the second gear day I have never had any trans problems, slippage, anything and no problems since that day.
I checked the trans fluid dipstick – no noticeable metal fragments.
The trans fluid and filter is due for a change.
The radiator fans are not turning on at all (overheating at idle or hard driving).

Is it possible that the combination could cause these codes?
The fuse is fine on the fans. Does that narrow it down to the relay I’ve read about?
Did I almost consider paying $1800 for needless work?

I'm thinking that your problems are related more by cause and compound effect. Not directly from each other.

If your radiator fan(s) stopped working then that would explain the heating during idle. The fan on my 96 just seized one day and stopped working... you may want to run some "jumper" wires from the fan(s) to battery make sure they are still good.
If your tranny is getting stuck on second gear, you and/or wife is having to rev the engine really high in order to maintain speeds over 40 miles per hour. That could be causing your engine to overheat and the problem is bein compounded by the fact that your fans are not working..

With regards to your tranny issue.. if the module is stuck. clogged or just malfunctioning perhaps just replacing it would be sufficient. It is not very expensive, especially compared to what the dealership wants...

Maybe someone else will jump in with some information on the tranny codes and some ideas..

also check the following url:

http://www.allpar.com/fix/trans.html

The po700 code means that a code is stored in the transmission controller. The po1767 code is from aftermarket code reader. The codes from the dealer are exactly as you stated. Overheat codes and a solenoid code.

These overheat codes can come from the fan(s) not working correctly. Its right on Mopar pinpoint charts, to make sure fans and cooling system working correctly. I would get overheat problem handled first.

One other note. At 100,000 miles this transmission is at then end of its life. Not being negative, its just they way its designed.


Stay cool

Just wanted to say thanks for the responses. I just ordered a new relay switch for the fan motors. Thanks to the posts I'm pretty sure that is the problem. BTW - we have not had any more transmission problems since we figured out the van was overheating during long idles. I'm praying we'll get at least another 20,000 miles before replacing the transmission.

Also check this:http://www.allpar.com/fix/codes.html. You might also check into installing an add-on cooler for the trans.