Transmission - no previous problems, now 100% slip
I have a 2000 Ford Taurus SES with 91,250 miles on it. The transmission has been flushed by Ford every 35k miles. I have never had a problem with my transmission in the past and no engine codes other than EGR (broken hose). Last week I was at a stop light two miles from my house heading out to take my boys to get haircuts. When the light turned green, the engine accelerated but the car did not go forward. I turned the engine off and back on, the car slowly moved forward to a safe place as the engine RPM was ~2000RPM.
After towing it home, I let it sit for a few hours then checked the fluid level and measured it, then I started the engine and let it run for 20 minutes - the fluid level dropped almost an inch.
I then dropped the transmission fluid pan and observed dark red fluid, no "burnt" smell, no metallics other than the metal "fines" attached to the magnet.
After raising the front end up and placing jackstands under the frame, I replaced the transmission filter and fluid. Leaving the front tires off the ground I decided to start the engine and move the shift lever into drive, the wheels began to turn. As I pressed on the accelerator, the wheels began to turn faster, then they slowed to a stop. I let the engine idle - no wheel rotation, then I turned the engine off and back on, put the transmission into drive and the wheels turned again for about 3 minutes, then they stopped. After they stopped and I press the accelerator I hear a "grinding" noise that I don't hear when I first turn on the ignition and accelerate.
My initial thought is that I have a fluid flow restriction - does this fall in line with the valve body change out as a possible solution?
Thanks in Advance,