Different size spare

[CanadianRyan]

So over a year ago a bought a low KM FL2 TD4 HSE for my wife to drive around and carry kayaks etc. It's been a great car so far, no issues. The other day I was checking tyre condition and thought I'd have a look at the spare as well. At first it appeared fine - spare factory rim shiny and new, and Continental Cross Contact tyre (from factory) also brand new without a mark on it. Then upon closer inspection I noticed 235 55 r19 on the tyre... WTF I thought... all my other tyres are 235 60 r18... so I have 18" factory wheels and tyres on the car and a brand new unused 19" spare which also appears to be factory.

Anyone have any ideas? It's had 1 previous owner and I've lost their details. From what I can find the HSE came standard with 18" wheels, so how it came to have a brand new 19" is beyond me. This also begs the question, does it matter? Will the 1.9mm increase in diameter be an issue if I ever have to use it? Thanks
Ryan

[theelms66]

Check out the tyre placard on the vehicle. Usually in door pillar or glove box lid. Because they are different profile 55 to 60 it equal out the circumference of the tyre . OR . Stand one against the other and check height difference. I sure someone will chime in with some tech advice.
Regards Pas

[Larry]

Tyre Size Calculator (https://tiresize.com/tyre-size-calculator/)

5mm difference in circumference (0.3%), 3mm difference in diameter (0.3%) = 1 x revolution per km difference.

I certainly wouldn't lose any sleep over it.[wink11]