Truck Won't Move In Forward Or Reverse

Truck Won't Move In Forward Or Reverse - Finally Disassembled

1994 model 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 almost 2 qts low on fluid. The fluid is red, clear & clean, and smells like new. The pan gasket may be leaking a little, nothing seems to be comming from the front seal.

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 move a little if you really rev it up but the transmission seems to be not really engaged or it's slipping.

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 who knows what. If thats all seems good pull the trans and change the TC?

Comments or suggestions? Are there any codes I should try to look for?

If you put the transmission in Neutral, can you push the vehicle a few feet on flat ground? If so, then that means everything 'downstream' from the transmission is okay.

It rolls fine in neutral.

Welcome to this forum! Did you use a 1/4" drive In/Lb torque wrench on the valve body bolts when you installed the valve body? Did you use the regular gaskets or the thicker ones? Was the governor ever serviced? It wasn't listed in your first post.

Negative on the governer, probably standard gaskets, and yes it was torqued with a calibrated torque wrench.

On some old valve bodies with high mileage, it's possible that they might be slightly warped, and the standard gaskets might not make a tight bond like the thicker ones.

check the vacuum modulator line, if the vac line has atf in it replace it, that would explain the missing fluid and the stalling, but I'm not sure that would cause it not to move under power?????

He said that the modulator was replaced in his first post.

Although the modulator is new I also suspected it may have pulled fluid and caused the engine to stall. The vacum line is clean and the valve/line held vacum with the hand pump.
I don't think it could keep the vehicle from moving. I thought it was more for kick down/passing gear.

Keep the ideas comming guys! Unless someone comes up with something different I'm sticking with my plan to inspect the pan for big chunks, pull and inspect the valve body & gasket, and if all that looks good I'll reluctantly hip-shoot the torque converter.

Update

Well Gents, It only took me three months to take it apart. It's a torque converter failure. I flipped it to drain it and it sounds like all the vanes sheared. Theres just a bunch of big chunks floating around inside.
The tranny is disassembled, it looks really good and clean. Other than the the thrust washer between the center support being worn out and the OD Center Shaft being grooved as a result it should be an easy fix.

Make sure that you flush the front cooler with cooler cleaner, and disassemble the valve body to get all of these small fragments out.

Will Do!