Ford Mercury Villager 1997 Owner's Manual page 296

Engine compartment main fuse panel
When checking fluid at normal operating temperature, the
fluid level should be within the crosshatched area on the dipstick.
When the vehicle has not been driven, and outside temperature
is above 50° F (10° C), the fluid level should be between the notches
on the dipstick.
Your vehicle should not be driven if the transmission
fluid level is below the bottom notch on the dipstick.
Adding Automatic Transmission Fluid
The fluid type is stamped on the dipstick. Before adding any
fluid, be sure that the correct type will be used.
Add fluid in 1/2 pint (0.25 liter) increments through the filler
tube to bring the level to the correct area on the dipstick. If an
overfill occurs, excess fluid should be removed by a qualified
technician.
292
WARNING