Based on your description, there is a possibility that you have an item caught in between the stainless steel spin basket and the plastic outer tub. Use a bright flashlight and check the inner spin basket holes for an item such as a screw or nail (or underwire) that could be sticking through one of the holes in that spin basket and protruding down into the tub. If you find an item in that area, then removing it may fix your problem.
If necessary, shine the light through the holes in the spin basket to try to find the item that is making the rubbing noise. Check the bottom of that tub to see if you can find the item. Pull back the inner lip of that rubber door but and check for an item that could be stuck in that area.
You can pull the drain pump filter and clean it as shown in the image below. That procedure is also in your owner's manual. Here is a link for the full owner's manual in case you need it:
. An item stuck in that drain pump can also make a loud grinding noise even though we are assuming that you have an item stuck between the spin basket and the outer plastic tub at this time. It is worth it to clean out that pump filter and maximize the flow of drain water in the washer. Check that pump area for any debris or foreign objects (coins).
Pull that dispenser drawer out and check the outlet of that component for an item that could have slipped into and through that dispenser drawer area.
Hopefully you will find the cause of that grinding noise using the tips described above. If not, you may need to have a service technician examine the washer. If you want to go further on your own, you can
unplug the washer
and follow the steps shown in this video to disassemble the washer and check further for the cause of that problem:
LG Washer Disassembly
. Keep in mind that the front door boot seal is held on by strong spring clamps. It is not that difficult to remove the spring clamps but they are challenging to re-install without the use of some special tools that a technician carries. If you need further help with this problem, reply with additional details and we will assist you further.
If you get to the point where you need to have a service technician examine and repair the washer, you can schedule service through this link:
Sears Home Services
LG Washing Machine Makes Grinding Noise ShopYourWay