Ford Mustang (2005-2014) Owners Manual: Washer fluid check

WARNING: If you operate your vehicle in temperatures below 40°F (5°C), use washer fluid with antifreeze protection. Failure to use washer fluid with antifreeze protection in cold weather could result in impaired windshield vision and increase the risk of injury or accident.

Add fluid to fill the reservoir if the level is low. Only use a washer fluid that meets Ford specifications. See the technical specifications chart in the Capacities and Specifications chapter.

State or local regulations on volatile organic compounds may restrict the use of methanol, a common windshield washer antifreeze additive.

Washer fluids containing non-methanol antifreeze agents should be used only if they provide cold weather protection without damaging the vehicle’s paint finish, wiper blades or washer system.