long delay going into forward gears

[gbodyman]

2004r i rebuilt couple thousand miles ago, i startes to i guess slip going into drive. It goes into reverse fine but od 3 2 1 when put into these gears wont go unless you hit the gas a lot and rev it up for a couple of secs. than it bangs into gear and is fine. Even when you come to a stop and start again it is fine. BUT if you put it into neutral or park and back to drive you must rev the gas than it bangs into gear again? Reverse works fine.

Thanks Ian