I need to know the difference between tow/haul and O/D. I thought my nitro was stuck in tow/haul. But the service manager at the dealership said the only thing tow/haul does is shift it in and out of O/D. There is no difference in my truck between tow/haul and normal mode in the lower gears it shifts exactly the same. My husband's truck has tow/haul and it makes it shift later in the lower gears. My truck shifts very late now (14mph) on slow acceleration in normal and tow/haul. And it hesitates at 40 mph and then shifts strange after that till about 60 or so. Sometimes it won't shift down when I slow down, and then when I accelerate again it won't go. I would appreciate any helpful comments. Thanks.