WHEN CODE U0073 APPEAR DE THE TRASMISSIN START HARD SHIFTING

Question

ON 2009 CHEVROLET EXPRESS 3500 6.0 MOTOR THE PROBLEM STARTS WHEN THE NEEDLE OF THE SPEEDOMETER DROPS TO ZERO AND STARTS MOVING UP OR DOWN THAT AFFECTS THE TRANSMISSION AND STARTS HARD SHIFTING AND THEN CODE U0073 OPPEARS

Answer 1

U0073 when this codes set the transmission communication  is suspended, here a link below it will come with a PDF format follow what your looking for is exactly a communication error, also there a transmission relay., replace that as a start

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