trans main seal or rebuild price quotes on 1990 Mercury Sable

transmission leaks fluid mainly when I take a long trip.I fill it up to safe checkered box on dipstick and it does not leak til i take a trip on the highway and the it leaks a spot about 4 inches by morning then during around town driving maybe a drop on the pan

Asked by for the 1990 Mercury Sable
check all your transmission seals and gaskets they maybe to dry or possibly broken