I had the opportunity to talk with a friend who is a sales person for Dodge motors co. He confirmed that the transaxle cooler is the transmission cooler.
The package includes heavy duty altenator, radiator,etc as well as the transaxle cooler. It also came with the wiring harness for the trailer hook-up.
He did mention The weight capacity max for that model is 3800lbs. I think we will be alright.