Some GMC Terrain owners report experiencing slow braking and unusual sounds, which may be attributed to several key components. Worn brake pads are a common issue, often identified by squeaking or grinding noises during braking; if neglected, they can damage the rotors, leading to more expensive repairs. Additionally, damaged rotors can exacerbate slow braking and contribute to these noises, necessitating replacement alongside worn brake pads to restore braking efficiency. Furthermore, while front control arm bushings do not directly affect braking performance, worn or damaged bushings can impact vehicle stability and handling, indirectly influencing braking effectiveness. Regular maintenance and timely replacement of these components are crucial for ensuring optimal braking performance and overall vehicle safety.

Some GMC Terrain owners report experiencing reduced engine power, difficulties restarting the vehicle, and backfiring during startup attempts. These issues may stem from a faulty throttle actuator control, which can hinder engine performance and restart capabilities. Additionally, a malfunctioning charge air pipe can contribute to these symptoms, including backfiring. To address these concerns, owners are advised to inspect the throttle actuator control for damage and check the charge air pipe for any leaks or cracks. It is also recommended to consult a certified mechanic or GMC dealership for a thorough diagnosis and necessary repairs to restore the vehicle's proper functioning.