2001 Ford Exp EB, 4R100 4x4.
220,000 miles on the transmission


It started going to work a couple of days ago. Truck shifts into 2nd and the rpm goes up without speed. I let off and reengaged and all is good. Next two days, not problem.

Today it happens again but I headed out. I loss 2nd gear with a flashing overdrive light. no check engine. I got it back home by using 1st gear to get it going and if I was over @48 mph I could get 3rd to grab for speed above 50 as long as I didn't let it to kick down to 2nd. In 2nd, it had no drive. At normal highway speeds, when I get there, the overdrive(torque convert lockup ) seems to work. The last of getting it home it seemed like 2nd gear was trying to work..

Codes:
P1744 Torque converter clutch system performance or mechanically stuck off
P1741 Torque converter clutch circuit Performance/stuck off
These could be the engine speed to wheel speed.
P0781 1-2 Shift
P1783 Transmission Overtemperature
Running in 1st gear...oil look, smells good
P1875 Transmission hall effect sensor power circuit short to battery
P1891 Transfer Case contact plate ground return open circuit

So my question is it a bad transmission or a bad 1-2 solenoid. Where do I start?

Thanks for the help

 

So I got a lot of lookers at this post.
I put the truck up in the air to pull the transmission out. The oil did not smell burnt but is no longer red. The plug did have some metal flake on it but I am sure the pan will be full.

First problem is getting the torsion rod out of the Torsion Bar Keys (pork chops). To unload them you can use a 2 arm gear puller or rent one from a parts store. I have PB blaster on the chops. If needed I can cut them off but they are pricy or built to lift the front. Pick a part but I still find a set I can pull.

 

Overdrive is fourth gear. Torque converter lockup is when the clutch inside the torque converter locks, eliminating slip in the torque converter. These are two different things.

I suspect that your intermediate clutch has failed. This will push debris throughout the transmission.

These codes almost always are due to stuck components. They get stuck from debris in the transmission.

That confirms that the 1-2 shift didn't happen when it was commanded and that the transmission has been over 275°F.
It's the transmission. You start by removing it, then either rebuild it or replace it.

With a failure like this, it is a good practice to replace any aux cooler and flush out the radiator cooler if equipped.

 

Mark, I am pulling it now, TY for the break down.

The pork chops are out. I used the cross member and a pickle fork against the inside of the crossmember. By putting a 3/4 nut on the shaft and the pickle fork on the other side I could preload the pork chop. I also used heat, not a torch but a heat gun and a temp reader and lots of PB blaster. The temp only got to @300 degrees. Once they broke loss it was easy to get them out.

With that out the next was the Transmission support, Skid plate, crossover pipe, both drive shafts...

What was left of the crossover clamp bolt. I just cut it.


The top down. Skid plate, Support for the suspension, Front drive shaft, Left cat and crossover, Transmission support. Note the cracks. I will pick up one from the junk yard or add patch plate.


These were the nuts holding on the left pipe. Yes the halve nut was holding the pipe. I didn't know what was holding the pipe on but I could feel the bumps. I put a socket on it and it came off.


I stopped there for the night. Every bolt and nut is being a pain coming a part. 18 years ago this was all put together and with the salt and crap here most is welded together.

 

The Transmission is almost ready to come out. I got the top drivers side upper bolt. The other side is the big question. How do you get to that one? I am pulling the left pipe now to see if I can reach up on that side. Letting the PB blaster do it work. The left was a 13 mm, a universal and two extensions. It came right out.

If anyone knows an "easy way" to get to the upper right...