185/65r15 vs 195/65r15 mileage/comfort

Thanks for the feedback guys! Just ordered the Michelin Energy Saver tires from tirerack in the OEM size. I decided on this route because I reminded myself that I bought this car strictly for saving gas, hauling the family and daily commuting and not to modify it in anyway that would defeat the purpose.

 

You may find like I did that the Prius will be much quieter with the Energy Saver's going from the Integrity. I started with 38F, 36R which was real smooth and tires ran quiet. Took them up to 42F, 40R ride was harsher as expected and noise increased slightly. Running 40F, 38R at the moment. I have about 900 miles on them so far. I repeat I have NO drop in MPG, but have seen a actual rise in MPG since I mounted the Energy Savers on our Prius.

Don't forget to use stick on weights when you balance the tires. If the TPMS light is on when you get the car back, push the button and let it set in ready mode for a few minutes. The light should then go off. It takes at least three minutes for the system to reset completely. I had that symptom and had to figure it out when I got ours redone. They probably moved the wheels around while doing the tire swap which helped to confuse the Prius TPMS system.

Ron

 

How does a wider tire change speedometer reading?

195---Tire width
65----Height of sidewall
15----Wheel diameter

 

Because 65 isn't how tall it is, it is the aspect ratio. 0.65*195 is how tall the sidewall is, so a 195 will be a bit taller than a 185. Its not taller because its wider, its taller because its wider and has the same aspect ratio.