I have an '09 Sport that has the "low profile-ish" tires that I will be replacing within the next couple of months (40K on the OEM's) and was thinking about a slightly larger tire to keep the road noise down and soften the ride.

But if I were to do that and were to get a flat and needed to use the doughnut, could that have some adverse effect since the spare would not be the same size as the rest?

 

No. 2 reasons.


1) Whatever size tire you get shouldn't be that big of difference in terms of diameter of tire vs OEM.


2) The doughnut spare should not be driven around a lot. Doughnut spare should get your car to where you can put a full-size tire on. That is its purpose and not much more.


Above comments are my opinion and I stand by them.


Hope you find it helpful.

 

Go with OEM.
Spare yourself all kinds of troubles.

 

even with the OEM tires, the donut spare is smaller in O.D. As has been said, it's just to get you someplace where you can get the tire fixed.

 

and a good practice (although a bit of a pain) if your front tire gets a flat is to put on of the good rears on the front, and put the doughnut on the rear... that way not only will diameter be the same, but steering will stay safe as well...

 

Get Michelin Premier A/S.

I've heard they're quite comfy.