The website address is Costcotireappointments.com It is a relatively simple process. You have to make an account by putting in your email address and a password. Once you do that you enter your order number off of your receipt. Then you select an appointment time. If you just drop it off, instead of it taking an hour, it could take all day.
Online website often not working
I would just drop it off and comeback when they are done if you have the means.
Easiest to just call the tire center for appointment. I too have experienced challenges with their online appointment system.
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