2007 Chevrolet Silverado 2500 Pickup Owner's Manual - Page 148

Tow/Haul Mode (Allison Transmission®) The selector button is located on the end of the shift lever. Turn the Tow/Haul on and off by pressing the button. When the Tow/Haul is on, a light on the instrument panel cluster will come on. See Tow/Haul Mode Light on page 262 for more information. Also see "Tow Haul Mode" under Towing a Trailer on page 423 for more information. Grade Braking and Cruise Grade Braking (Allison Transmission®) Grade Braking and Cruise Grade Braking assists when driving on a downhill grade. It maintains the vehicle's speed by automatically using a shift schedule that uses the engine and the transmission to slow the vehicle. This reduces wear on the brakes system and increases control of the vehicle. The system constantly monitors the vehicle's speed, acceleration, engine torque, and brake pedal usage. It detects when the truck is on a downhill grade and the driver's desire to slow down by pressing the brake. If your vehicle has an Allison Transmission®, it may have a Tow/Haul mode. Tow/Haul mode adjusts the transmission shift pattern to reduce shift cycling, providing increased performance, vehicle control, and transmission cooling when towing or hauling heavy loads. 148