I drive a 2000 Dakota Sport Ex Cab 4wd with the 4.7. It has been a great ride for several years until recently.

The Transmission started slipping. We tore it apart and rebuilt it and had to put in a new shift module pack (I think thats what you call it) while it was torn apart. I was able to get an older model with the black connector that was refurbished rather than the newer version with the white connector.

Since reinstalling everything it seems to drive ok and shift ok but the engine stalls everytime I come to a stop with it in drive. The truck acts like you are stopping a standard trans without the clutch pressed in. If I am at a stop and put it in drive, the RPMs drop to around 300 and the engine dies. It does not do this in Reverse and generally takes about 5-10 seconds after the engagement before the idle drops.

Here is the kicker... with Air controls in Defrost or A/C turned on everything works great. I know both of these situations the idle is ramped up but not sure why the lower idle causes the trans problem to exist.

Is there a programming or some other issue I need to look at? BTW the module pack was replaced because of hard failure codes even though bench tests were good on the module. I have no codes now.

Thanks for any help or suggestions.

 

I had a similar problem to yours where I would come to a stop and the darn thing would just shut off and I'd have to start it and hold the gas down a bit before it would catch itself at idle.

I checked out my air filter, and the casement it was in was all filled with dirt and gravel. I had a hole. I cleaned it out and patched up the hole (with aluminum tape) and I haven't had a problem since.

 

Sounds to me like your torque converter clutch is remaining locked as you come to a stop. That would explain why it feels like a standard transmission stalling your engine. No idea how to cure it, except that it's likely an issue with a wrong signal being sent to the transmission control module. The fact it works OK with A/C on indicates some electronic signal is getting confused.

 

I have suspected the torque converter myself but I am not sure if that would fix the problem or is there a re-programming or something else I should do first?

If it is a programming issue, I will have to go to the dealership. If I need to replace the converter first and then still do the programming .......

One additional symptom happened today as I was trying different things for isolation purposes... A fast de-acceleration to a stop causes the engine to stall every time. However, stopping slowly increased the odds of not stalling. BTW... the low idle is about 500 while the fast idle is about 750 according to the analog tach...

As previously stated, with the A/C selector switch on, and idle kicked up, it did not stall at all.

 

Low tranny fluid will cause the TC to stay locked when stopping.

 

Yes low fluid can make the engine stall. Mine idles low (500 rpm) also I suspect a bad IAC but have not checked into it yet.