205/55/15 MPG

[ctrj]

Are you accounting for the speedo error? You're speedo/odometer is now reading slow.

[MadMax]

Originally Posted by ctrj

Are you accounting for the speedo error? You're speedo/odometer is now reading slow.

That is assuming the speedo was correct in the first place, which it isn't.

The more accurate way to find your speed is with a GPS. I found that my larger tires made the speedometer on my Yaris more accurate (same happened with my Jeep), which means that your MPG probably wasn't as good as you thought with your stock tires if you used your speedo to compute it.

But expect to take a hit with the larger tires, I did and it is significant compared to the stock wheels. With my 215/45ZR17s Riken Raptors on my 08 auto hatch I get 36-38 MPG during the summer and 32-34 during the winter with easy driving. I was hoping for better, but that's not bad and I can live with it because I love my Yaris so much. Plus, it goes around corners like it's on rails so there is a lot of fun in driving it.

Cheers! M2