15 inch tire question

Our Canadian "Touring" model has the 17" wheels. Every winter I switch them for 15" snow tires, but for the rest of the year we stay with the stock 17". I believe there's a mpg penalty with the 17's, but not serious.

I think by far the responses are going to be to stick with 17", and I'm on that side: if only because that's what the car came with, seems a shame to swap them out right away. Also, they look good. FYI, the models with 17" wheels also have different steering setup: for starters the lock-to-lock fo the steer wheel is less than models with 15", ie: the steering is a little quicker. Turning radius is bigger though.

 

The 17s are heavier so handle rough roads worse and result in slightly poorer mileage.
Replacement tyres are more expensive.

The 17s give greater grip as the contact patch with the road is larger. This also results in heavier steering, but this is compensated for by a stronger power steering system.
Greater grip also means better stopping in an emergency and better handling on curvy roads.

-I- wouldn't mess with the stock setup, but you can do whatever you feel appropriate.

 

I Agree with David.

There is a mpg penalty to the 17s but if you don't drive much the monetary difference is quite low. If you do drive a lot then the economic hit over the lifetime of the vehicle can be quite large (assuming you change to more efficient tires and drive well). In my testing I have observed at least a 3mpg difference in mpg between 17s and 15s. If you start hypermiling the difference increases because 15s roll so much easier than 17s. If you switch from the OE 15" tires to more efficient 15" tires the gap grows even larger and could save you a couple thousand over the lifetime of the vehicle.

In summary, if you are the type to just get in and drive the car and you don't drive a large number of miles per year then stick with the 17s. They are safer and the stability of the car is better if a bit less comfortable. My girlfriend is considering a new Prius. If she gets one I will swap her to 17s just for the safety and control factor.

 

The sole reason I bought a level 4 and not the level 5 was that the level 5 came with 17" wheels. I did not want 17" wheels because of the negative attributes associated with them, i.e. less comfortable ride, lower MPG, higher tire replacement cost, less choice in replacement tires. If you do switch to 15" wheels and tires it would be interesting to hear from you whether you think it was worth the effort and expense.

 

You'll lose even more mpg with short mileage stop and go traffic BUT it won't cost you much annually.

 

We test drove both a 15" and 17", before buying the latter. To be fair the drive in the 15" model was at night, and the first drive. But the second drive in 17" the car felt much more secure/planted.

(could actually be nothing: the car feels just about the same with the 15" snow tires we use each winter: Michelin X-Ice)