It is a simple fix and at the same time the most difficult fix I have ever done.
Washer model is WM3670HVA.
There are several video tutorials online but this one from RepairClinic.com was the one that really helped. It’s not for the same model but most of it applied the same way.
Many tutorials show how to replace the boot seal without disassembling the machine. These did not work for me. Disassembling the machine was relatively easy compared to trying to put the seal and inner ring inside the door.
Part number MDS47123619 did not work for me despite the description saying it was compatible. Not sure if incompatible or if I was installing it wrong. Ultimately part number MDS657369-IJ5 worked. It costed 50 dollars on eBay.
I did buy and used a 383EER4004A washing machine spring expansion removal tool. It’s a specialized pliers to expand springs. It helps immensely with the most difficult part of putting the expansion rings back around the seal. It costed 10 dollars on Amazon.
While putting the inner expansion ring, it’s easier to have the ring closed already and then using the pliers to expand the spring and putting the ring in place. The tension of the spring would always bend the hoop holding the spring. Using locking pliers I could bend it some more so I would have about one minute before it would bend it open.
The inner door boot seal should be done in a way that the water falls into the drum. I was doing it wrong, creating a gap and the water leaks when the machine operates. This also makes it harder to close the ring. The inner door boot seal should “bite” the white part of the drum and not “hug” it.
Using gloves would have saved me from several small cuts in my hands. Specially when dealing with the heavy front door.
This was a surprisingly difficult fix. Ultimately the replacement worked and the machine was back in business.