Ford 1998 Mustang Owner's Manual page 107

Driving
Once through the water, always try the brakes. Wet
brakes do not stop the vehicle as effectively as dry
brakes. Drying can be improved by moving your
vehicle slowly while applying light pressure on the
brake pedal.
Driving through deep water where the
transmission is submerged may allow water
into the transmission and cause internal
transmission damage.
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