Search new + high quality used 255 40 ZR21 Michelin tires online, starting at: $47.99. 255 40ZR21 Michelin models in stock: 4. All season: 3. Summer: 5.. Selling all used tires at discount costs. All used tires go through 2 layers of inspection on specialized equipment. One year warranty + free shipping on all inventory ;) Happy shopping!