Tire Size Calculator

The 50-series has a taller sidewall: 225 × 0.50 = 112.5 mm vs 101.25 mm for the 45-series. The 50-series diameter is about 0.88 inches larger, or about 3.3% taller. This is at the edge of the recommended 3% limit. Your speedometer would read slow (actual speed higher than indicated) and odometer would under-count. Clearance and fitment should be verified before making this swap.

A wider tire has a larger contact patch with the road, which can improve lateral grip and braking on dry surfaces. It also adds rolling resistance (slightly worse fuel economy), increases unsprung weight, may not fit in the wheel well, and can cause issues in snow (narrow tires often perform better in deep snow by cutting through to hard surface).

The load index is a code number indicating the maximum weight each tire can support at its rated inflation pressure. Index 94 = 1,477 lb; index 100 = 1,764 lb; index 106 = 2,094 lb. The tire on your vehicle must meet or exceed the maximum load specified on the door-jamb sticker. Installing a tire with a lower load index than required is unsafe and may violate insurance and warranty terms.

The original equipment tire size is printed on the yellow sticker inside the driver's door jamb, in the owner's manual, and sometimes on the fuel cap. It will show the required size and cold inflation pressure for front and rear (which may differ). Some vehicles run staggered fitment with different sizes front and rear.