I tried tow haul mode last weekend pulling my motorcycle trailer and hauling camping stuff. I got way better gas mileage using tow haul than I did doing the same trip a few weeks before. 19mpg vs 16.3 And I was using B20 on the 19mpg trip and Drews Brew on the 16.3. So does tow haul just change the way it shifts or does it change something with the ECU also? If it is really better on gas, can you use it all the time?

 

I hope your not putting gas in your truck

anyway, tow haul holds the gears a bit longer and locks the torque converter up quicker.