GENERAL MOTORS issued a recall on the ENVOY and TRAILBLAZER models

Certain 4WD vehicles were built with a range shift collar in the transmission transfer case that contains cracks. This condition could result in a complete fracture of the range shift collar and subsequent loss of vehicle forward and reverse gears, and the inability to maintain "park" position. This increases the risk of a vehicle crash resulting from unintended movement of a parked vehicle. Correction: Dealers will replace the transfer cases and update the control module calibration.