Tyre size

[akkers5]

What’s the difference between these 2 tyre sizes:
255/40 R18 Y
255/45 R18 Y

If you had the 255/40 before and you replace with 255/45 what is consequence?

[PaulV]

Plug the numbers into something like https://www.willtheyfit.com/

[Smint]

Presumably they fit ok, with no clearance issues.

Check in your handbook or on the car's tyre label to see if the new size is standard for the car, if not it might be worth running the change past your insurer first, they might want a small extra on the premium for modification but some insurers may not play ball at all.

[MustangGT]

akkers5 said:

What’s the difference between these 2 tyre sizes:
255/40 R18 Y
255/45 R18 Y

If you had the 255/40 before and you replace with 255/45 what is consequence?

You are increasing the rolling circumference by 3.86% which is more than I would consider. This will affect your speedometer, causing it to read a 3.86% lower speed, which may, or may not, cause your speedo to under-read the speed at some speed. This is an offence legally. It will also affect your milometer reading by the same amount and could affect your fuel consumption. It is probably not enough to foul the bodywork anywhere.

Your insurance company may also not like it (as somebody else posted).

[akkers5]

Actuall the car drives ok but when I turn a full lock it appears to be catching the body somewhere.