1994 Ranger purchased a year ago w/130k. The tranny at the time had sluggish shifting and harsh rev engagement when cold. There was no metal in the pan at that time, just the typical gray sludgy stuff one would expect to see. I installed a shift kit, changed the servos, modulator, filter, and fluid. The transmission had been perfect since.

Last night my daughter calls, She said "it stalled as she was coasting to a stop. It restarted but the engine stalled everytime she tried to put it in Rev or OD. She kept messing with it and it stopped stalling but wouldn't move forward or reverse in any gear".

I brought it home this morning, it was 1 1/2 qts low on fluid. The fluid is red, clear & clean, and still smells like new. The pan gasket looks to be leaking a little, nothing seems to be coming from the front seal. There were no bad or unusual noises coming from the transmission. While under the truck it faintly sounds like fluid flowing under pressure from inside the pan when the truck is in gear but I can’t say that’s unusual. Regardless it doesn’t sound alarming or like anything that wouldn’t be normal.

I've topped the fluid, When I put the shifter in any gear you can feel what I can only call engagement but the truck wont move as it should. Stepping on the gas the vehicle trys to move and actually will start to move if you really rev it up but the transmission seems to be not fully engaged or it's slipping real bad. While doing this the transmission is not loading down the engine. I didn’t keep trying to make it move fearing if something was torn up I would be making it worse.

Not being a tranny person and for a lack of better ideas instinct tells me to pull the pan and look for metal. If the pan is clean drop the valve body and look for broken springs or stuck valves.
If thats all seems good pull the trans and change the torque converter and flush the cooler?

Comments or suggestions? Are there any codes I can pull or anything in particular I should try or look for?