Search new + high quality used tires online. Size 235 50 ZR18 starting at: $51.4. Tires in stock: 151. Available brands: 35 with 53 models. All season: 138. Summer: 13.. 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!