M_Boats: transmission cooler

I tow a couple times a season in a moderate (Michigan) climate on flat roads. I tow about 200 miles, or 400 miles a season. Otherwise, I use my tow vehicle only to launch and retrieve my boat on a moderate-incline ramp. I have an M17. I'm considering a '95 6-cyl. 4X2 (2-wheel-drive) Dodge Dakota Magnum with an automatic transmission. Will I need a transmission cooler?