Why Does My Transmission Shift Hard? If you have a heavy-duty truck with a Manual Shift Transmission, there are several reasons why you may experience Why Does My Transmission Shift Hard. One possibility is the shift rails in the cover are binding making the shift lever move hard. To fix this condition the shift cover would have to be taken off and reconditioned so that the shift rails can move easily. Another condition that can cause this, you would notice that certain gears would shift hard, and the rest of the gears would shift easy is a Bent Shift Fork. To repair this condition the shift cover must come off and be taken apart and a new Shift Fork installed. Another reason you may experience a Why Does My Transmission Shift Hard is internal failure of the transmission shafts or gears. If the transmission experiences a hard shock load to the gearing it can put a slight twist into the Main Shaft or break the teeth off the gears. If you are looking for Heavy Truck Repair Near Me or Transmission Repair Near Me the Team at Widrick Truck & Diesel is ready to help you give us a call or contact us through our website.