Codes P0740, P0753, P0758, P0785, P2761, and P2101, Transmission?

2005 GMC ENVOY
160,000 MILES • 3.6L • 6 CYL • 4WD • AUTOMATIC
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GMFABS
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Hello, thank you all in advance for solutions. I had several codes come up. P0740, P0753, P0758, P0785, P2761, P2101. I had 2 solenoids changed, the 2 in front of the transmission, new fluid and filter. The original problem was shifting first and second gear. It would move but very hesitant and very slow. But if I shifted manually from first second and third it ran fine. So, the solenoids got changed, and I'm still having the issue with it shifting and actually driving. The harness did not get changed nor did the other solenoids. Please help, I have no idea what else to do, neither does my mechanic. Thank you
Aug 21, 2023 at 10:28 PM
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STRAILER
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With all of these code I would clear them, then turn the key on without starting the engine and re-run the cdoes, we are looking for the most prevalent code, if no codes come up start the engine then shut it off and run the codes again.

P0740: Torque Converter Clutch Solenoid Circuit

P0753: Shift Solenoid A Electrical

P0758: Shift Solenoid B Electrical

P0785: Shift/Timing Solenoid

P2761: Torque Converter Clutch Pressure Control Solenoid Control Circuit/Open

P2101: Throttle Actuator Control Motor Circuit Range/Performance

Also, is the transmission fluid burnt?
Aug 22, 2023 at 1:07 PM
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GMFABS
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Thank you so much for your answer. I did look up all those codes. I cleared the codes with a scanner. After driving the vehicle again, the codes still pop up. I can manually shift the vehicle and it seems to work better. The biggest problem is first and second gear, those are the solenoids that I had replaced. The fluid was not burnt, but it was very dark and there were metal shavings in the pan. I'm wondering if it is possible the solenoids are defective, or can the harness be bad? Thank you again.
Aug 22, 2023 at 7:11 PM
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STRAILER
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Yes, it sounds more like the harness is bad I would check the main wiring connector at the transmission and the wiring in general for damage/corrosion. Also, it could be a bad PCM.
Aug 24, 2023 at 10:41 AM