Ford: trani not engaging, mercury sable, problen

Question
  Hey Ragu, my wife has a 1990 mercury sable. A few days ago she stopped at a stop sign then tried to go again but the trani would not engage. I checked the fluid level which seems fine. When I put the car in drive and rev the engine the car will move forward the slightest bit. When I put the car in reverse and rev the engine it will move in reverse but only the slightest bit. I'm not a very experienced mechanic and the book I have for this car does not even mention transmission in it. Any help is greatly appreciated.

Answer
Ryan  sorry to say  but it sounds like your trans is gone and 1990 was all buy themselfs 89/91/92 wont work.but first what i want you to do is go to the car and ck the trans fluid level with the car off see were it is on the dipstick then start the car up and see if the level changed if it does the front pump is working if it doesn't then the problen is internal