Of not working and trans not shifting
I have a 1999 Tahoe I was driving on the highway
about 70 my odometer drop to zero and I lost all
power to the trains I'm pulled over put it in park and
pulled off and only have first gear what could be
Some most common things are, shift solenoids getting stuck, TCM programming failure, transmission wiring failure. A tranny shop will be able to plug in electronically and run a separate set of test to determine if it is solenoids, control module or an internal pressure problem.
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