G
G
Guest
Lots of bad information here.
Tow haul does not lock out overdrive on a modern transmission. Some old transmissions like the E4OD in 1990 era Fords had an overdrive off switch that did lock out overdrive, but there aren’t many of those ancient trucks out there seeing regular use.
The modern tow/haul switch simply moves the transmission control strategy to an alternate map, giving you different shift strategies for a given torque input / pedal position. The transmission will remain in a lower gear longer and downshift earlier. It will also effect downhill / coasting calibration.
Modern transmissions don’t have to be locked out of overdrive in hilly terrain. The calibration takes care of the transmission. I never understood why it upsets people if the transmission downshifts going up an incline. That’s it’s function, in part.
What he said.