2005 dodge Dakota transmission over heating changed fluid then put on oil cooler still heating up and sticks in third gear still goes to n and reverse but wont drop gears when taking off should I look for tranny or might it be converter going bad?

 

That sounds like a tranny issue to me. I had the same thing happen in my '98. I had to replace tranny.

 

How many miles?

 

I don't know where you live, but at the shop I work at we do Trans flushes with bg chemicals. It works wonders. Find a shop in your area that uses bg and have them flush your Trans