I have a 2009 Touring model and I'm getting studded tires on rims for the winter here in Anchorage. According to the guys at the tire shop, I have the option of 15 or 16 inches wheels/tires. I was considering the 15 inch setup due to the price, but can anyone see any issues with going with the smaller size?
To be precise, bigger wheels -- usually heavier -- and slightly wider tires burn more gas. Technically, this is correct. Theoretical MPG reduction may be as much as 4% or maybe 2 MPG. Keeping the tires filled to 42psi front/40psi rear goes a long way to overcome this. On either size wheel, the choice of new tire can result in a loss of up to 6 MPGs -- there are usually other pluses such as improved handling, less noise, better braking, etc. In everyday driving the combination of variables such as temperature, traffic, topography, route, tire pressure variations, and even driver attention level make it virtually impossible to "isolate" this small fraction of overall MPG/FE. A more significant difference is there are considerably fewer tires on the market to choose from for the OEM 16" tire size. There are many threads discussing the relative merits of the two wheel/tire sizes and numerous tires. The search tool is your friend!
Thanks folks, I figure on losing some MPGs with the studs, but maybe I'll gain a few back going from 16" to 15".
