Can you replace P26570R16 with P245R7516?

No, you cannot directly replace P265/70R16 with P245/75R16 due to differences in width and aspect ratio. The first number indicates the tire width in millimeters, and the P265 tire is wider than the P245 tire. Additionally, the aspect ratio (the second number) affects the tire's overall diameter and handling characteristics, which will differ between the two sizes. Always consult a tire professional or refer to your vehicle's specifications before making any changes.