To change the oil in a John Deere, warm the engine oil, turn off the engine, drain the oil, take out the oil dipstick, and add fresh engine oil. Check the oil level by putting in the dipstick, and then fit it into its housing. Take care not to overfill.
Before changing the oil in a John Deere, let the mower engine run for 10 minutes to warm up the oil. Turn off the engine, and park the vehicle on a level surface. Ensure that the parking brakes are locked. Open the cap of the oil drain valve located under the mower hood by turning it counter-clockwise. Allow all the oil to drain into a drain pan placed under the valve.
Remove the oil dipstick from its housing, and clean it with a rag. Add fresh engine oil in the housing. To avoid overfilling, insert the dipstick for five seconds, and take it out. The oil level on the dipstick should not go beyond the full mark. Replace the dipstick in its housing, and let the mower engine run for 10 minutes.
Check the oil level again with the dipstick, and add oil if necessary so the level touches the full mark. Fit the dipstick snugly in its housing. Close the mower hood, take out the drain pan, and dispose of the drained engine oil.
Follow the owner's manual procedures for model-specific instructions. Buy oil specific to the John Deere model as mentioned in the manual.