245/45R18 vs 245/40R18: Gas Mileage & Performance Comparison
* Below is a comparison table. Assuming 2 tires of the same manufacturer, material and tested on the same road conditions.
| 245/40R18 | 245/45R18 | |
| Wet/Snowy Roads | Better Traction | Reduced Traction |
| Rough Terrain | Reduced Stability | Smoother Ride |
| Handling/Steering | Less Responsive | Less Responsive |
| Gas Mileage | Good | Better |
| Road Noise | Quieter | Quieter |
| Cost | Less Expensive | More Expensive |
Can You Replace The 245/40R18 With The 245/45R18?
No, both tires have the same rim diameter, but the 245/45R18 has a bigger overall diameter than the 245/40R18 which is 3.62% (0.96-inch).
When you want to replace a different tire size, as a rule, for the rim diameter, you will need to be sure that your tires and rims are an exact match, e.g. a 245/40R18 tire will only fit on a 18″ diameter rim.
You Can check our tools and charts below to find your size:
