Greetings! My wife and I own a 2017 QX50 and the original Dunlop tires are about worn out at just under 30K miles. They are 225/55r18s and I'd like to change to a 245/50r18 if that doesn't create any problems. Does anyone know if such a change in tire size would adversely affect the performance of this car? I don't see any issues with fender fit or tire rub but are there factors I'm overlooking? Thanks for any advice/suggestions!

Welcome to Nico! Your new home away from home! ..

I'll let someone else cover the tire question though

Thanks for the welcome Palmer! I'm hoping someone will come along with some tire info soon.

If you compare the two, the overall diameters are roughly the same (within 0.4%) so you shouldn't see much difference in speedometer reading.
The tire is wider by about 0.7", so you will obviously see some effects from that - a bit more tramlining on highways, perhaps slightly higher steering effort, maybe a bit worse performance in snow (since narrower is better) but I wouldn't imagine it will be a major difference. Any particular reason you're looking to change the size and not go with the OEM sizing?

Thanks for the reply! I had used a tire comparison chart to check out the dimensions and saw that the diameter was very close to the same. We have very little snow here so that isn't a real issue. I wanted to explore going to a wider tire because I thought it would look somewhat better and perhaps maybe handle a bit better as well. I believe the wider tire would enhance the rather pugnacious looks of the QX50 but I didn't want to sacrifice performance either.

We have been leasing cars since 1998 and have leased mostly Nissan products in that time span including a '01 Xterra, three Maximas ('04, '11, '13) an Altima Coupe ('08) and this Infinity for the past three years. This 2017 QX50 is the first leased vehicle we've kept post-lease and I'm looking forward to enjoying it for a few more years.

Gotcha. Yes, assuming there are no clearance or rubbing issues, you definitely could get a bit more lateral grip and a handling improvement out of 20mm wider tire. Also forgot to mention that you could see a slight decrease in gas mileage and also some increased road noise with a wider tire. If you do a lot of highway driving, you will notice this a bit, but it might not be an issue for you.

I am also interested in changing out my rim and tire set up for my 2017 QX50 RWD. I was interested in putting 235 19's up front and 245 19's out back. This is only going to be my daily driver.

What rim size and offset would you guys recommend?