Transmission problems

[ograptor]

Well. On my way to the shop to replace my bulkhead fitting, the dreaded wrench light came on. It wouldn't shift out of second when I got off the highway, so I put my code reader on it and came up with code p0741. Torque convertor clutch circuit performance stuck/off. Is this the lead frame issue? Or a solenoid issue? I need to get this right because it's my daily driver. Thank you in advance

 

[bwep]

What happed after you shut the truck down and restarted did it drive normal?
When my lead frame failed it would hold gears, bang into gear and start out sometimes in high gears. I would shut it down and restart it would function normal for a short period of time.
Also, your replacing the fitting going into the transmission, if that's loose that would be a problem.
Make sure you do a quick check of the wires running near the exhaust, there has been a few that had the harness melt causing issues.
I have 2 F-150's and both needed lead frame replacements

 

[ograptor]

Shutting it down and restarting it didn't change a thing. Apparently there's a tsb about a seal between the valve body and the case, and the separator plate between the valve body halves. If that's not it, then it's a total valve body replacement, because apparently on the 5.4, the solenoids and lead frame are part of that whole thing. At the tune of 1800 bucks. It's at my mechanic now, ill update when I hear back from him

 

[ograptor]

So. The tsb states that I need to change the square seal between the valve body and the case. It also says to change the separator plate between the 2 halves of the valve body. So this is gonna happen. I'll report back.

 

[ograptor]

Ok. So, here's what we did. Replaced the square seal between the valve body and transmission case. The original one was cracked in 3 places. Installed new separator plate. Installed a shift kit from Trans dap? Also installed the cooler bypass valve. Changed a shift solenoid. Installed a Dorman pan with a drain plug. New filter and fluid. Picking it up in a few minutes

 

[ograptor]

It drives soo good now.

 

[TomDirt]

How do you crack that seal? From hot/cold cycling? Did you save the broken parts?

 

[pat247]

I watched a video a few years ago that recomended replacing all plastic parts when doing transmission repairs. I believe it said there were four total.

 

[ograptor]

I have no idea how it happened. I chalked it up to 140k of mileage. I did not save the part. It was in rough shape with 3 big cracks. Luckily, no pieces missing. Between that, a burned up shift solenoid, the aftermarket stuff we put in it, it's better than new. It still needs to be flashed according to my mechanic, but that's happening tomorrow