Tow prep pkg, what does that include?
 

can anyone clarify what I am getting for $265 and whether it is worth it? Two identical vehicles one with tow prep and one without, therefore one is 265$ less. I may tow a 2000 lb trailer once a year. Is there any wiring harness or similar benefit? Or, just a tranny cooler and radiator cooler?

RGSW is correct, the rear Hitch Receiver and wiring are additional even when equipped with "TO" towing prep package.

I like the piece of mind of extra cooling capacity.

Same here, ended up getting tow pkg. also, I thought tow capacity was 3500 without and 5000 with but it is 2000/3500. Would rather have the beefed up version especially given heat in Florida.

2016/2017 RX Tow Package Info
 

Couple of specification and appearance differences between 2016 and newer RX 350's
that have or don't have "TO" Towing Prep Package. The Coolant Capacity is 9.9 liters
(10.5 US quarts) with the HD Radiator vs. 9.0 liters (9.5 US quarts) without.

Quick visual difference is to examine the lower right and left fascia "vents" The Driver's
Side (left side) is open and you can see the aluminum heat exchanger when equipped
but is a closed (fake) grill without. The Passenger Side (right) is closed up either way.

Attached are a couple shots forward from the Driver's Side wheel well that clearly shows
the aluminum heat exchanger when equipped and open space without.

I have the tow pkg and ordered curt 13272 and wiring connector today. Great price on Amazon for $120 w free ship and 15$ for the connector. Install looks easy for everything. Where will I find wiring connector, on the passenger or driver side and is there anything that needs to be removed to locate it?

Check out this thread.

wiring
 

lol. I'm not reading 5 pages of that nonsense to find out what side the plug is on, I will wait for someone to help out.

Then I suggest doing a search.