94 5.0 GT Automat. Tran Slipping

1994 Mustang GT V8 5.0 Automatic 94,000 miles

I bout the car with 92,000 miles and at the start when put into Drive it would hesitate a sec but than work fine. After driveing 3000 miles across country I now notice that when I slow down or stop and start up again it takes a little bit for it to go into gear. When starting from a stop I have to tap the gas till the gears catch, its moving at an idle pace while I'm doing this. If I give too much gas it'll come into gear hard. Now it doesn't do this all the time, about 20% of the time it'll work just fine from a stop.

I changed the fluid and filter. The fluid wasN'T burnt and there was no metal shavings in the pan or any evidence of mechanical wear. The filter had no particles in it either. I refilled using treatment which doesnt seem to help it too much.

just to add, it shifts into reverse just fine with no hesitation. And it shifts into the passing gear hard, I accelerated fast to test it and the car reved wildly before it "hit"