Search new + high quality used tires online. Size 315 40 R21 starting at: $30.06. Tires in stock: 317. Available brands: 6 with 22 models. All season: 281. Winter: 8. Summer: 28.. 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!