Oct 2010 we rebuilt this transmission due to loss of 1st gear and OD, along with engine warning light with code P0755 shift solenoid problem. Since that time, we have been back to shop multiple times (under warranty) as engine warning light comes on with P0770-which is "lock up clutch is not functioning right. There are no drivability problems. TCC only drops about 150 RPM at L/U engagement-no problems experienced and fluid is clean. Replaced valve body. again drove >50 miles and code again appearing as a pending code. Torque converter replaced same problem after about 50 mile. A pump in transmission also replaced. They have also checked out the computer and it is working correctly. We are going in to replace rebuilt for new transmission next. Then if light still on with same code, they will consider it electrical and that is not under the transmission warranty. The engine light and codes had never occurred during the 2 yrs we had the car, prior to the transmission problems. We are all stumped by this problem. I would love to have the car’s transmission warning lights stop throwing codes and transmission continue to work well. Any ideas?
There’s 2 ways to rebuild an automatic transmission.
A soft rebuild meaning new clutches, seals, O-rings, etc. and a hard rebuild meaning all of that plus bushings, solenoids, converter, and so on.
It sounds like you got the former.
They replaced the valve body but what about the solenoids that make all of this work?
Just offhand, this transmission overhaul sounds like it was on pretty shaky ground from the get-go based on continuing to go back and forth on it.
They used bushings, A40 series pump, Transtar master rebuild kit, Transtar solenoid kit, A140/1240/241E, neutral safety switch and filter, it the initial rebuild. The transmission appears to be, and feels like it is running fine, but the code (pending code) still shows up.
What about the possibility of a malfunctioning brake light switch? (Should be tied in with the TCC operation.)
Interesting. I will followup with shop and see what they think prior to dropping a new transmission in. Thanks.