Code uo101 Looses comunication with trans and will not shift

Hello, first it means the code tells you that there is lost of communication with the TCM ( traction control module ). Check all fuse link to that module an if everything is fine buy another module an let it be able to communicate first. That cat will never change because it needs to know the vehicle speed for it to change since it's automatic transmission..

just as precaution, have you been changing the trans fluid as recommended. Start off simple, check the fluid level, change the fluid and filter if due. Read the owner's manual for how to check the fluid level. Check for any loose wiring connectors that go to the trans. IF this is no help. Get to a reputable trans shop.

about 7L to 8L .don't flush.

Hi there:
DTC U0101 - TCM Message Unavailable
I suggest to check description and solution details HERE.

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check main plug on trans for insulation on wires falling off wires and maybe touching together

Take it to Autozone and scann for codes. Get back to me with the codes and I'll take it from there.

The transmission has an epc (Electronic Pressure Control) solenoid in the trans that when it looses power or fails it goes to full throttle pressure. You need to have the system scanned, check for blown fuses and have someone go into the trans information and see if the epc is getting power.

break down of the codes is

po303 - that would be a misfire on cylinder 3
uo101 - cant communicate with TCM
uo107 - lost communication with throttle actuator control module

The problem is a known issue with the 1 to 2 shift at hard throttle. The fix is a repair of the entire 2nd clutch assy. in the transmission. There is a TSB about it released by Chevy. It will need that rebuild for the sudder to go away, or you can try and let off it at shift to stretch more miles out of it.

any codes? the trans computer will store them. also the engine computer this is an obd2 car autozone can scan for free