2004 Ford Taurus

I bought it 4 months ago and have had only a few small problems like a hard shift when I throw it into reverse once in awhile, or a delay in shifting when I switch from reverse back to drive. Anyway my check transmission message came on the other day and then went away, but after checking the fluid and seeing that it was dark I decided to change it.

I dropped the pan, cleaned it out, changed the filter, reassembled, and the added about 4 quarts of fluid back in. I then fired up the car and now it wont shift into any of the gears??? The transmission dipstick says it is slightly overfilled right now but I imagine it will take more fluid if I could get it to shift.

I used mercon V fluid which the manual said to use. I drained approx 7-8 qts of the 13 it holds. I then added in 4, started up the car and shifted to try and circulate some of the fluid. The car wouldnt shift so I thought no big deal just add more fluid. Added 4 more (8 total) and still nothing.

I went down and listened for noises while shiftting. Some of the gears I hear the whining like it is trying to engage but still nothing.

Anyone every had this problem or have any suggestions?

BTW only 45k miles on the car