Cracked Wheel / Rim and Tire Sizing Question

[aisherwood]

Hello Everyone!

New here, owner of a 2023 CT5-V v6. Running the Michelin Pilot Sport A/S 255/35/20 tires.

I've owned the car for 10 months now and have a good size crack in my wheel and a leaking tire from it. I'm worried that if I replace the wheel / tire as is, I'll be in the same boat a year from now.

Any recommendations with downsizing to 18's potentially and getting a 245/45/18? I'm a little worried about the aesthetic difference and cost of replacing all my wheels/tires.

I'm not particularly car saavy and not sure how large of a buffer the 45's would make over the 35's. Happy to hear about others experiences!

Any thoughts would be appreciated!

 

[shbox]

I think the 245/40-19's that come on the 5V are just right. 35/20's ride harsher. Recently went to Continental ExtremeContact DWS 06 Plus and couldn't be happier with the change in ride comfort over the stock A/S RFs I had.

 

[Black Bengal]

Sorry to hear about the wheel issue. I agree that the 19" wheels are aesthetically good for the CT5-V. My '26 CT5-V has Pilot Sport 245/40 ZR19s, which I plan to swap out for a non-run flat tire at the first opportunity. I'll probably stick with Michelins (I always do). I wonder if you would have the same wheel issue with non-run flat 20" tires? Also, I have one of these spare tire kits (link below). The same kit works for 19" or 20" wheels. It takes up trunk space but is very well made and can be driven at normal speeds for longer distances. I've heard that non-run flat tires are quieter and ride better, but I'm looking forward to one day verifying that myself. Cadillac CT5 Spare Tire Kits. Light Alloy, Compact Size | Modern Spare

 

[shbox]

I've heard that non-run flat tires are quieter and ride better, but I'm looking forward to one day verifying that myself. Cadillac CT5 Spare Tire Kits. Light Alloy, Compact Size | Modern Spare

You can take that to the bank.