The contact owns a 2006 Mercury Grand Marquis. The contact stated that while stopped at a stop sign and attempting to accelerate, the vehicle failed to accelerate as intended. The contact stated that there was a loud clanking sound coming from the vehicle. The vehicle was towed to an independent mechanic where it was diagnosed with transmission failure. The contact was informed that the transmission needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was approximately 85,000.