I have a 2008 Outlander that is fitted with 225/55/R18 tyres:

1. Is it possible to fit a higher profile tyre like a 225/60/R18 or a 225/65/R18?
2. What would the pros and cons be?
3. Would the higher diameter damage the gearbox or anything else?
4. Would it invalidate my extended warranty?

I have geard that a higher profile tyre would give a smoother ride.
Also, in South Africa, the 225/55/R18 is a very expensive tyre.

Regards
Leonard