2010 GMC Yukon Owner's Manual - Page 23

Range Selection Mode The vehicle can automatically shift to lower gears as it adjusts to driving conditions. When 3 (Third) is selected, 1 (First) through 3 (Third) gears are automatically shifted by the vehicle, but 4 (Fourth) cannot be used until it is selected. The Range Selection Mode controls the vehicle and engine speed while driving down a hill or towing a trailer, by allowing you to select a desired range of gears. When you move the shift lever into M, the transmission will default to M4. In this gear range, effective engine braking occurs at speeds above 45 mph (72 km/h). Pushing the minus (−) button on the shift lever reduces the gear range. In the M3 gear range, effective engine braking occurs at speeds above 35 mph (56 km/h). In the M2 gear range, effective engine braking occurs at speeds above 25 mph (40 km/h). In the M1 gear range, effective engine braking occurs at speeds above 10 mph (16 km/h). When operating in M (Manual Mode), Auto Stop is disabled. For better vehicle efficiency, operate the vehicle in D (Drive) not M (Manual Mode). Cruise control can be used while using the Range Selection Mode. The Range Selection Mode controls the vehicle's transmission. To use this feature: 1. Move the shift lever to the M (Manual Mode). 2. Press the plus/minus button to upshift or downshift selecting the desired range of gears. A number displays next to the M, indicating the current gear that has been selected. The number displayed in the gear indicator is the highest gear that can be used. 3-9