Tire size...

[joedudz]

I have 245x65 x17 tires on 17 inch wheels,
What size tire would I need to change to utilize an 18 in wheel, as not to affect the speedometer
245x ? x18 ... Im guessing 60?

 

[swshawaii]

One of many tire size calculator sites. This is the first that came up.
https://tiresize.com/calculator/