2005 Dodge ram 1500 2wd Transmission works fine some days. Then when I shift to drive, it starts off in 3rd or 4th. Rpms about 2k, goes very slow. It will pick up speed, but I have no passing gear, it doesnt shift up, or down. I can manually shift to Low1, and Low2. No error codes picked up. Transmission has been replaced(used, at a dealer) same issues. When I drop it off at the shop for a week, no problems found and it drives great...pulling my hair out. 130k miles

 

Sounds like either a valvebody issue or the PCM is not operating the solenoids properly.