Mark, this is directly from the 2013 Ford Taurus manual. I have a 2013 Lincoln MKX and it reads similar excepte I put my keyless ignition in the accessories position.
"Vehicles Equipped with a 3.5L Engine
Note: Put your climate control system in recirculated air mode to
prevent exhaust fumes from entering your vehicle. See the Climate
Follow these guidelines if you have a need for recreational towing, such
as towing your vehicle behind a motorhome or truck. We designed these
guidelines to prevent damage to your vehicle after it is hooked-up to the
recreational vehicle or tow dolly.
You can tow your front-wheel drive vehicle with all four wheels on the
ground or with the front wheels off the ground by using a tow dolly.
If you are using a tow dolly, follow the instructions specified by the
equipment provider. If you are towing with all four wheels on the ground,
see the following instructions.
You can tow your all-wheel drive vehicle with all four wheels on the
ground or with all four wheels off the ground using a vehicle transport
trailer. Do not tow your all-wheel drive vehicle with the front wheels off
the ground (by using a tow dolly) and the rear wheels on the ground.
This causes damage to your all-wheel drive system. If you are using
a vehicle transport trailer, follow the instructions specified by the
equipment provider. If you are towing with all four wheels on the
ground, see the following instructions.
If you tow your vehicle with all four wheels on the ground:
• Tow only in the forward direction.
• Release the parking brake.
• Place the transmission in position N.
• Do not exceed 65 mph (105 km/h).
• Start the engine and allow it to run for five minutes at the beginning
of each day and every six hours thereafter. With the engine running
and your foot on the brake, shift into position D and then into
position R before shifting back into position N."
Doesn't say a darn thing about leaving it running.