Cadillac 1995 DeVille Owners Literature page 117

NOTICE:
When using concentrated washer fluid, follow the
manufacturer's instructions for adding water.
Don't mix water with ready-to-use washer iluid. Water can
cause the solution to freeze and damage your washer fluid
tank and other parts of the washer system. Also, water
doesn't clean as
well
as washer fluid.
Fill your washer
fluid
tank only 3/4 full when it's very cold.
This allows for expansion, which could damage the tank if it
is completely full.
Don't use radiator antifreeze in your windshield washer. It
can damage your washer system and paint.
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