Rep Power: 0

My hatchback runs 235/40R18 tires. Potholes and curbs are a constant danger for wheel damage.......and the tires are extremely noisy. Considering changing to 235/45R18 tires, but not sure I'd have sufficient room. Anyone have any thoughts on this tire size change? Thanks

 
Rep Power: 511

If you want more sidewall, consider going 17s or even down to 16s. Some sedan models came with 215/50-17's and some with 215/55-16's, and if they 11thgens are as similar between body styles like the 10thgens were, you shouldn't have any issues fitting those.

215/50-17s would give you a +.5% speedometer error (negligible, but actual speed would be higher than indicated)
215/55-16 would give you a -.5% speedometer error (also negligible, actual speed lower than indicated)

The 234/45-18's you're looking at would give you a +3.7% speedometer error. I personally like to stick to ±1.5% or less (of course, the closer to 0% the better) when I shop around for different than OEM tire sizes, then compare that calculated tire size to readily available options.

 
Rep Power: 0

Great information, I'd not even thought of speedometer error. My biggest concern was (is) wheel damage due to the low profile tires. Most everything I see on the road now a days are low profile......maybe I'm just getting too old to deal with the newer fads? Thank you for the advise. Lee

 
Rep Power: 511

https://www.wheel-size.com/calc/

This is the site I use to see all differences between tire sizes I'm comparing. Most people back in the day didn't give a crap about speedo error, just that they wanted bigger rims and rubberband low profile tires. When I was researching my first wheel upgrade, the concept of speedometer error came into play, and became a big part of what I look at when I want to change tire sizes or profiles. Another thing indirectly affected by it is your odometer, since erroneous speed indication would output different travel distances