Ive had this truck for over a year now, and it has done this ever since ive owned it. i had the tranny flushed new filter installed and synthetic fluid put in (not cheap). but the issue still goes on. what it does is, when driving it acts like a normal truck, but when you let off the gas to slow down or whatever, the rpms drop straight down to an idle. where as most vehicles when you let off the gas the rpms stay where they were when your driving. but i dont know why mine drop to idle. also, if you let the truck sit for more than 2 days it will lose line pressure, as in if i start it after 2 days and put it in gear, it wont move for a bit until it gets pressure again and will take off. i prevent this by starting the truck and putting it in neutral for about 30 seconds before i take off and its fine doing it this way. but i would think it shouldnt lose line pressure after 2 days of sitting. ive included a short video of what my truck does when driving and letting off the gas. any help, ideas, or information would be appreciated. id like to get this figured out while its still nice out to where i can fix it....im leaning towards the possibility of the torque converter going out. although it still shifts like normal, and the torque converter still locks up normally.

http://www.youtube.com/watch?v=Kznz54ycwEg

 

Looks pretty normal to me. When you let off the gas, the TCC seems to be unlocking, so, engine will drop back down to idle. RPM's are right for the speeds though, so I do believe the TCC is working correctly.

If the check valve has been removed from the tranny cooler line, (right up by the radiator, soft line with a few metal fittings that plugs into the lower side of the trans cooler in the rad) then sitting for a few days will allow fluid to drain out of the torque converter. As these transmissions don't charge the converter in park, that behavior is normal as well.

No problems there. Just typical dodge trans behavior.

 

yes i did remove the restricter. as my fitting had a crack on the factory cooler and was leaking fluid. so i run an external tranny cooler and took out the restrictor....but it did this losing pressure deal before i bypassed the restrictor

 

Take it to a reputable tranny shop and have them put a scanner on it to check pressures.