Quote Originally Posted by 2010AveoLT View Post
... after a few minutes of a Cold Engine SCREAMING at a Speed that Should only be seen when Blasting down the Interstate at 70 MPH did it shift into 4th.....
No degree in Automotive Technology here - just a low level, amature mechanic. But I've been driving for over 40 years, and never have blown an engine. Perhaps a big factor is that I've never pushed any vehicle until it comes up to temp - just very moderate rpms and speed. The link below describes how Chrysler programs their TCMs, using temp(s) as the key inputs. Seems like there must be some type of similar programming done for every make.
Perhaps you just had bad luck with your Plymouth. But OTOH, maybe you should think about your driving habits, and consider backing off a bit until the engine comes up to temp. Not intending to be rude or obnoxious here - just trying to offer some friendly JMHO advice.

Jeep Grand Cherokee Transmission Shifting Problem