A 6.0L does not have and Overdrive Lockout. It has the 5 speed Torqshift transmission and a Tow/Haul Mode button. The transmission uses all 5 gears when in this mode. It will hold a gear longer and may not shift in to 5th as soon as normal, but it will use 5th. It also keeps the Torque Converter locked and does not us the coast clutch as much to allow for engine braking. When I tow it is in THM and I let it do its thing.... THM is also nice in the hills empty .............
