Costco is offering members:
$150 off when you spend $700+ on any set of 4 Michelin tires with installation.
$110 off when you spend up to $699 on any set of 4 Michelin tires with installation.
Note that this is a new deal (previous two deals were $70 off + $0.04 installation and $70 off + $40 off installation). This offer is $150 off the price of the tires with installation at the regular price of $79.96.
You can order online (search by vehicle, license plate, size, or item #) or in-person at the Costco Tire Center at your local Costco Warehouse. I was there a couple days ago and the guy was nice enough to give me a heads up that I should wait until this deal went live on Wednesday.