So I have a 04' Dakota with a 3.7L and 42RLE transmission. The transmission has been shifting hard but no check engine lights are on. If it was a bad speed sensor or shift selonoid would it throw a code? I have changed the filter and fluid already and put in a new transmission pan as the old one was leaking. I thought this may have been the cause of the hard shifting but it has not stopped. Any ideas if it sounds like a sensor or an internal issue?