Hi again,thanks to Melatv advice my shift motor problem is solved. I have another question. I want to change the rear gear oil in my 2007 honda rancher trx420te. I bought the correct oil.The service manual say’s to replace the sealing washer on the check bolt, O-ring on the filler cap, and the 3 bolts on the skid plate. Are all these bolts necessary to replace just to change the oil? Thank you again for all your help.