If you don't have the mechanical fan, hitch, wire harness or full size spare then chances are the vehicle wasn't equipped with the tow package. Nothing to worry about though, it can be added.
The transmission is cooled through the A/C condenser, I was unable to find a different one so I don't think the tow package made a difference there.
The "sway control" as some call it is a function of the vehicle's stability control, nothing different there either.
Mopar calls the mechanical fan a viscous fan. You'll need the fan, clutch and hardware to install it.
The mopar receiver is the one you want as it tucks up nicely out of the way compared to the aftermarket ones.
You'll also need to purchase a trailer brake controller or prepare for increased maintenance on the brakes or the inability to stop.
Mopar recommends a load leveling hitch and for good reason. The stock springs are squishy and a trailer of any real size will point your front end to the sky.
They sell two different wire harnesses. A 4 wire and a 7 wire one. You want the 7 wire one. The receiver has a place to mount it already welded to it.
That said, additional transmission cooling is a very good idea as well as a temperature gauge.
This info is based on the experience I had while improving my KK's towing capability. I still have to add the fan and I'm undecided about the auxiliary cooler.
2010 KK Sport, Detoures Knucklebone & backbone, smittybilt XRC 10, rigid led lights, R/L sliders & rack, cb, EMT2, R/K 15x7, OME, JBA, mopar skids & hitch, headlight covers, 4.10's and TruTracs