Service bulletin - After the software update, some vehicles based on how they are driven (extreme conditions) may still experience ATF deterioration after updating the PGM-FI system and the shudder may return. The problem is typically diagnosed as a bad torque converter (TC). There is no damage to the TC, but because the ATF has deteriorated, it needs to be
changed even though the ATF Service Due message has not appeared. Make sure the software is updated by referring
to the INSPECTION PROCEDURE.