Search new + high quality used 235 40 R18 Sumitomo tires online, starting at: $64.7. 235 40R18 Sumitomo models in stock: 3. All season: 2. 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!