Ignition Transmission Lock Check
While parked, and with the parking brake set, try to turn the ignition to LOCK/OFF in each shift lever position.
• The ignition should turn to LOCK/OFF only when the shift lever is in P (Park).
• The ignition key should come out only in LOCK/OFF.
Contact your dealer if service is required.
See also:
Online Owner Center
Manage your vehicle (U.S.) at gmc.com. Click on “Owners,” then “Manage My GMC/Owners Login.”
Information and services customized for your specific vehicle — all in one convenient place.
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Low Traction Mode
If your vehicle has the Allison Transmission, or the Hydra-Matic 6-Speed Automatic Transmission, it has a Low Traction Mode that can assist in vehicle acceleration when road conditions are slippery, s ...
Introduction
The names, logos, emblems, slogans, vehicle model names, and vehicle body designs appearing in this manual including, but not limited to, GM, the GM logo, GMC, the GMC Truck Emblem, and SIERRA are ...