car wont take off in D. I must put it in S then shift to S3 then s4. no overdri on 1991 Acura Integra

when i try to shift in D at 50 mph it doesnt shift. car is fine for first 30 miles. then has this problem

Asked by for the 1991 Acura Integra
It's a simple transmission, try getting the oil hot, drain it and use Honda ATF-Z1, check the level of oil with the engine off (unlike most other cars) if problem persists it's most likely a failing transmission.