I have to get new tires. OEMs have worn out. I have a 2006 Prius. I read from one user that he put on Kumho Solus KR21 and switched to the larger size of 195/60/15 and had no problems with any decrease in MPG. Yet I read another user did suffer lower MPG due to heavier tires. I am torn between the MIchelin MXV4 or the lesser expensive Kumhos. The Kumhos got great reviews on tirerack, but I'm concerned going up a size and about gas mileage. Does anyone know how to find out if Kumhos have low rolling resistance like the Michelins and what the tread life is? Anyone out there with good or bad experience with Kuhmo tires and/or what happened when you enlarged your tire size? Thanks Gena
I replaced the OEM tires with Goodyear TriplTred. They're fine tires and will probably outlast the vehicle and myself. The 195/60 size has approximately 2% greater circumference, hence mileage numbers shown on the MFD and the odometer reading will be affected. However, the speedometer reading is now right on. I found that the increased weight of the tires (12 pounds each greater than the original tires) has an adverse effect on mileage, but it's not terrible (52MPG to 49MPG). However, the change in the feel of the steering, acceleration and coasting is significant. I wouldn't call it a bad change, but then, I might be overly sensitive, and you might not be able to tell the difference (my wife can't). I don't have any experience with the Kumho or Michelin tires, but I think that you should be fine with either one. If you're still concerned, go with the lighter one.
Economy is more about rolling resistance than weight, personally I'd pay the extra for Michelins. The Michelin energy tyres are designed to provide good performance and low rolling resistance, I didn't see anything about rolling resistance on Kumho's web site. 195/60 15 is standard size for Prius all over the world except North America, I'm getting 54 to 55mpg on Michelin Energy XM1 195/60h 15 without much effort.
I agree with Patsparks above, with tires its more about the rolling resistance than weight. Now with wheels, weight is a consideration, but not so much with tires. The low rolling resistance tires can, and do make all the difference in the world. In addition, I very highly recommend staying with the OEM size of tire. Wider tires put more tread on the ground, hence more resistance, hence less MPG. I've just purchased a set of Michellin Hydroedge in the 205 width. That has hurt my mileage a bit. Stay with the 185 if possible. Actually later this year I believe Michellin is supposed to be coming out with tires that have up to 50% lower RR than their lowest tire as of now. That's what I'm going to wait for. Best of luck. check the tire threads on the Mods forum or the Fuel Economy forums.
i used 185/65r15 michelin harmony and they are awesome with an 85K warranty, I get over 50mpg with them and they are quiet & wear evenly. however, I have steel wheels and 195/65r15 bridgestone blizzaks on right now for the winter and with the cold weather I'm below 40mpg increase weight &/or increasing rolling resistance will result in decreased gas mileage and less horsepower making it to the road. this is only worth it if you put on some cool-looking 17" or 18" rims on the car. but keeping your boring stock 15" rims and going with a tire that will hurt your fuel economy doesn't make any sense to me, why do it?
