GMC Acadia transmission locks up in low gear causing RPMs to spike and vehicle speed to drop to 20 mph, with ongoing repair delays on GMC Acadia

Some GMC Acadia owners report experiencing transmission issues, including the transmission locking up in low gear, which causes RPMs to spike and vehicle speed to drop to 20 mph. This frustrating problem is often linked to transmission slipping, leading to power loss and unpredictable gear changes. Additionally, fluctuations in RPM can be attributed to the Idle Air Control Valve malfunctioning, which affects air control during idling. While changing the transmission fluid may seem like a solution, it may not resolve the issue if there are underlying mechanical problems. Owners also report signs of transmission failure, such as strange noises, slipping, or hesitation during shifting, indicating the need for prompt attention. It is recommended that affected owners consult with a qualified mechanic or dealership to thoroughly diagnose and address these transmission concerns to ensure the safety and performance of their GMC Acadia.