1996 Ford F150 Owner's Manual - Page 330

Adding windshield washer fluid Use specially formulated windshield washer fluid rather than plain water, because specially formulated washer fluids contain additives that dissolve road grime. For safety reasons, washer fluids containing an appropriate antifreeze such as methanol should be used in freezing weather (temperatures below 32˚F [0˚C]). State or local regulations on Volatile Organic Compounds (VOC's) may restrict use of the most common antifreeze, methanol. 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, and windshield washer system. If you choose to use a windshield washing solution that must be mixed, follow the manufacturer's mixing instructions. Improperly mixed solutions may freeze unexpectedly. NOTE: The addition of shields to the front of the vehicle, as used to deflect bugs, may also adversely affect the washer system from delivering fluid to the windshield. Devices such as bug shields are not recommended to be added to your new Ford product. 331