Trans slipping or rather Torque converter lockup problems.

[JKBarger]

Hello all, I have a 2001 Dodge Ram 4X4, 318 with an automatic trans. I though I would share my plight in order to hopefully keep others from much aggravation and needlessly spending their hard earned cash rebuilding transmissions. This started out as a slight annoyance where I noticed while driving at 65mph the tach would run up from the normal 1800rpms to 2300rpms and feeling the transmission was slipping. The minute I would put the drive train under load such as accelerating or running up or down any type of grade the problem would go away. I gave the truck to the local Dodge dealer to troubleshoot the problem. I was given the truck back after they said the governor circuit was bad and that solenoid was changed out. After giving them $468.00 and driving off the problem was still there. Back to the dealer I went. They tried to find the problem and couldn’t but remapped the PCM hopefully taking care of the problem. This time I made the mechanic drive the truck when I picked it up and you guessed it there was the problem big as life for him to experience. He said that it felt as if it was the two/four clutch pack that was failing. I was sold a transmission rebuild after talking them down from the $2800.00 they were going to charge me to $2000.00. After the rebuild the mechanic took it for a drive and the slipping problem was still there. They went back into the trans looking for the problem and even replaced a slew of engine sensors and even the PCM with no luck. At least I lucked out because they didn’t charge me for any of those extra parts. All the new sensors and PCM were installed as warranty items under the 80,000 mile emissions warranty clause my truck only had 79,000 miles on it. After a couple of days of troubleshooting and a full tank of fuel they finally turned it over to Dodge tech support. They ran several data downloads and sent those into Dodge for their investigation. Before Dodge could get back to them the mechanic that was working on the transmission found the problem. There is a five volt signal cable internal to the transmission that carries the signal telling the torque converter to lock up or unlock that had rubbed against the valve body and was shorting out. I was told that when the drive train is not under a load, i.e. maintaining a speed on a level road, the five volt signal tells the torque converter when it’s necessary to lock or unlock. When the drive train is under a load the torque converter works normally. That’s why I only felt this on the highway maintaining 65mph on a level road and didn’t while the drive train was under load. Now the truck runs normally with the wire replaced and secured in a way that this will not happen again. The mechanic said that he will be notifying Dodge so that this will become a known problem and hopefully be documented as a tech bulletin. I hope this helps those experiencing the same problem.