2011 Chevrolet Silverado 1500 Regular Cab Owner's Manual - Page 331

Driving and Operating Tow/Haul Mode (Allison Transmission or Hydra-Matic 6-Speed Automatic Transmission) Turn the Tow/Haul Mode on and off by pressing the button, located on the end of the shift lever. When the tow/haul is on, a light on the instrument panel cluster will come on. See Tow/Haul Mode Light on page 5‑29 for more information. Also see "Tow/Haul Mode" under Towing Equipment on page 9‑105 for more information. Vehicles with an Allison Transmission or Hydra-Matic 6-Speed Automatic Transmission have a Tow/Haul Mode. The 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. 9-47 Grade Braking (Allison Transmission or Hydra-Matic 6-Speed Automatic Transmission) The Grade Braking shift modes can be activated by pressing the button on the end of the shift control lever. While in Range Selection Mode, Grade Braking is deactivated allowing the driver to select a desired range of gears. Grade Braking is only active while the Tow/Haul Mode is selected and you are not in the Range Selection Mode. See "Tow/Haul Mode" listed previously and Manual Mode on page 9‑45 for more information on the Range Selection Mode. Grade Braking assists in maintaining desired vehicle speeds when driving on downhill grades by automatically implementing a shift schedule that utilizes the engine and transmission to slow the vehicle. This reduces wear on the braking system and increases control of the vehicle. Grade Braking monitors vehicle speed, acceleration, engine torque and brake pedal usage. Using this information, it detects when the truck is on a downhill grade and the driver desires to slow the vehicle by pressing the brake. This feature is active when the exhaust brake is enabled (if equipped). Also see Towing Equipment on page 9‑105 for more information.