Why does my transmission shift real hard ?

Possible failed engine mounts, driveline slack, ( faulty axles ), internal gear component wear, or: The transmission controller raises line pressure in response to a failure indication, ( slipping ), this is accomplished using an Electronic Pressure Control solenoid, which normally changes line pressures due to different engine loads, & gear ratios selected by the driver, including reverse. The EPC may stick in a high pressure position with debris contamination, which is only resolved with transaxle rebuilding or replacement. Recommend consulting a professional technician.