The vehicle has electric cooling fans. The fans spinning at low speed during most everyday driving might be heard. The fans can turn off if no cooling is required. Under heavy vehicle loading, trailer towing, and/or high outside temperatures, or if operating the air conditioning system, the fans can change to high speed and an increase in fan noise might be heard. This is normal and indicates that the cooling system is functioning properly. The fans change to low speed when additional cooling is no longer required.