Most definately not! The Tow/haul mode doesn't lock out your top gears. It gives the motor some extra RPM's before shifting, allowing the trans to hold the gear without bogging from low RPMs. Also, tow/haul downshifts a gear each time you tap the brakes for engine braking (works awesome). I have heared that under normal driving, 1st gear is not used because it is so low. I don't know if this is true (my trans shifts too smooth and quickly for me to notice, even with a tach) but first is definately used in tow haul. Really a pretty cool feature.