99 4r70w automatic transmission started it up this morning and it went in reverse but had to rev a little till it went to drive, everytime I stoped I had to play with the throttle till it would go into gear. After going to parts store for some fluid because I was about 3/4 quart low it won't go to drive at all but I still have reverse.

 

Sounds like your tranny finally gave out.

 

yep. overhaul time. Good luck.