I have a 97 F-250 HD Powerstroke with automatic tranny.
I need to pull a trailer with my car on it. The two will weigh about 6,000 pounds together.
I have always heard to tow in drive, but the owners manual says to tow in overdrive.
How does everyone weigh in on this?
I will be towing from Indiana to Idaho, and don't want to tear up the transmission before I even get to the mountain pass.

 

6K isn't a hard pull.. Towing in O/D is fine, but what you don't want to do is let it 'shift hunt' in and out of O/D continually.. If you come against a tall grade and/or available power loss due to load, head wind, altitude ect, that causes the trans to shift to often out of O/D, then cancel it out until conditions change.. The service intervals for the E40D is 30K and might be good to have it in that service range prior to a pull..