Search new + high quality used 225 50 ZR18 Kumho tires online, starting at: $47.99. 225 50ZR18 Kumho models in stock: 3. All season: 6. Summer: 1.. 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!