Product review (5 stars): So Easy Once the Steps are Outlined!! Save HUNDREDS-Do it Yourself.
This hose from LG was the original part. Water line runs from the water valve to the water filter assembly.  Took 10 minutes to replace using the following steps:
1. Turn the power off to the unit.
2. Pull the unit out.
3. Shut the water off.
4. Remove the lower access cover.
5. Take the valve off the unit.
6. With the valve removed there is a clip that is under the ring that goes around the tube. Remove the horseshoe clip. Push in on the ring that goes around the tube toward the water valve and pull the tube out at the same time.
7. Go to the front of the unit and remove 1 screw at the front of the water filter housing.
8. Once removed, slide the water filter head forward.
9. Disconnect the small tube with the elbow on the back of the refrigerator.
10. Take the tubing out of the clips on the back of the refrigerator.
11. Once this is done you will be able to take the entire water filter head out.
12. This will allow you to be able to access the compression fitting on the back of the filter head to remove the tube like the one on the water valve.
13. You will then reinstall in reverse.  Hint: Make sure that you push the tubing back into the fittings all the way.