My 98.5 2500 dodge has trouble in the third gear. When I get up to 45 mph the rpm moves from 2000 to 1500 to 2000 to 1500 back and forth fairly fast until I get over 60 mph. The truck is a automatic. What do I need to fix?!?!

 

I hear that my govner and my transition are telling each other different messages that's why this is happening