Flash: Drivetrain Control Module (DCTM) - Transfer Case Operational Enhancements
This bulletin involves flashing the Drivetrain Control Module (DCTM)
Owners may indicate that they have experienced one or more of the following symptoms: Moaning or groaning noise while coasting and/or during a very light acceleration around 5 to 8 mph (8 to 13 kph). The SERV 4WD message appears and the vehicle shifts from 4WD to 2WD. Binding of the front driveline while turning on steep grades at speeds around 3 to 5 mph (5 to 8 kph).Surge/Shudder at speeds greater than 50 mph (80 kph).