Quote Originally Posted by steved View Post
My observations:

My 2012 2500HD (6spd auto) runs:

- 160*F unloaded, outside temperature over 90*F.
- 185*F towing 3k pounds, loaded with roughly 1k pounds, outside temperature over 90*F, and hilly terrain.
- I have seen 200*F one time, and that was towing at max GCVW in the mountains, outside temps around 75*F.
- It might approach 170*F if I'm sitting in heavy traffic.

I rented a 2013 1500 (4spd auto) last week:

-180*F unloaded at 75*F, highway
-200*F unloaded at 90*F, highway
-220*F fighting heavy traffic at 75*F

Between the two: I'm pretty sure the 1500 did not have a stand alone factory trans cooler, my 2500HD does. And the 1500 would unlock the converter on the highway (pulling a grade) where the 2500 would have either held the gear or would have dropped a gear (converter locked regardless).
I think the trans cooler is dependent with the packages on the truck. My 2013 1500 has the Heavy-Duty trailering package which does include a locking diff and a trans cooler. I also believe there is an oil cooler.