We purchased a used transmission because the original transmission went out. The one we purchased was very clean like it had been rebuilt. It was a headache!!! Since we have replaced the transmission, when the Dodge Dynasty is cold it will shift fine. But, once the transmission heats up to operating temperature, the damn thing stops shifting. I worked at the coperate office for Dodge,Jeep,&Chrysler and this is a on going known problem. The only the things that I have not replaced is the vehicle speed sensors. Since the transmission is electronical it makes it a bitch to figure out which is causing it to not shift.