Transmission slipping 1st and 2nd gears with overdrive light on. 1995 ford explorer?

When I come to a complete stop I give it gas and as soon as the gear engages I let off gas right away and slowly gas it then. If you were to just floor it in these first 2 gears it will slip. It drives fine and shifts fine in higher gears. Any ideas? 125,000 miles on this car.

Unfortunately back then Ford sucked at making transmissions (I've had 2 old Fords both had tranny problems) there's no easy way to fix it your just going to have to replace it or the car

Any automatic transmission that slips is toast! The clutch packs get fried really fast and by the time you drive it home when slipping it's time for a rebuilt tranny.