I have a 03 concorde w/151k on the clock that while coming to a slow or stop it decides to downshift itself , lets make a list of the possible culprits. the trans fluid looks red and not dirty. so that part looks good. (dont know how to get the codes) what sensors or what trans parts would cause this? yea im frustrated and dont wanna drive a hour away in traffic and about to just start replacing sh*t. so lets name some possible parts that have been known to cause this prob. im thinking i have a clogged catalytic converter , just dont think this would cause down shifting , however im not a chrysler tech.

 

It's supposed to downshift as the car slows to a stop. That's not a problem. If the downshift is rough, that could be a problem. If you recently disconnected the battery, the trans may be in the process of re-learning which should go away after a while.

 

sorry Boss , i did not elaborate well enough. when it down****s in first - it stays in first , so when you start to take off again from a stop your rpm's go way high , im forced to pull over and shut the car off and re-start. no recent batt issue's.

 

So the problem isn't that it downshifts, the problem is that it won't upshift out of first sometimes. If you want to avoid wasting money on unnecessary parts, then by all means get into the computers and get the codes. Almost certainly there will be error codes in there.
Take it to a reliable transmission shop and have them read the codes. It's nuts to throw parts at without any idea what's wrong.
And trans fluid that's red in color may or may not be any good. At 151,000 miles it's long overdue for a change.

 

^ makes sense , i was just frustrated , just kinda hoping there were only 2 or 3 sensors that could be the culprit of this problem. but yes your example of the trans problem sounds better and correct , its just not up-shifting after the normal down shifting from a normal slow down , or stop. So you have talked me into taking the long drive hour and 45 min to Knoxville to get these trans codes. im sure it will save money in the long run. I would let the g/f do it for me , due to me being very busy , however g/f is blonde and who knows what kind of info she would come back with from the trans shop?