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Michelin Harmony Tires

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by rdoucette, Oct 25, 2005.

  1. rdoucette

    rdoucette New Member

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    Have been doing a lot of research on replacement tires for my 04. I now have 34K miles, and expect to get about 3 more months out of them.

    I have been trying to find rolling resistance data on the most promising tires, which is very hard to come by. Fortunately, Consumer Reports just released, in their November issue, a listing of all-season tires which includes the short list of possible replacements.

    One of the tires that has superior rolling resistance is the Michelin Harmony. Some here and elsewhere have reported that they have not taken a mileage hit with these, and some on TireRack have reported a mileage increase.

    I am seriously considering putting them on my Prius, but would appreciate any firsthand experience with them. Mileage, handing (especially in dry conditions), braking, etc.

    Thanks! :)
     
  2. jayman

    jayman Senior Member

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    In October of 2004 I hit standing water on the Trans Canada after a torrential rainfall. At the time I was exiting to take #12 south, and the only thing that kept me out of the ditch was the VSC.

    The Integrity has poor rain/water performance. I swapped to Harmony on the recommendation of my Toyota dealer.

    There was no difference in fuel economy. Ride seemed a bit softer at the recommended inflation. Handling seemed a tad better. Tracking at highway speeds was a bit better. A bit quieter on smooth cement or pavement, the Integrity howled the Harmony has a high pitched whine.

    It's a good 3-season tire, snow and ice traction is poor compared to a dedicated studless winter tire. After 18,000km treadwear appears to be very minor but I'm easy on tires anyway.
     
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  3. rdoucette

    rdoucette New Member

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    Good news!

    I put on a set of Harmony tires last Thursday, then drove 600 miles to/from the Ft. Worth area.

    Initial report is that the tires give AT LEAST the same mileage as the OEM tires, and possibly better.

    Handling is fine, a bit softer "turn in" than the Goodyears, which seems to tame the "twitchiness" in the steering. They ride a bit harder at 44/42, but I want to compare them at the same pressure I was using before. If the mileage is actually improved (it seems to be about 2 mpg better then before) I may try them at 40/38.

    Will report back as I have more experience with a few tankfulls.
     
  4. rdoucette

    rdoucette New Member

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    Here's an update on the Harmony tires... :)

    I just put new tires on my 04 after 35K miles. Still had 6 to 7/32
    on the center of the Goodyears, but the edges were almost bare (as
    has been reported here and elsewhere). I was afraid that water would
    have nowhere to go and perhaps cause easy hydroplaning. Some have
    reported this problem with the Integritys as they wear.

    I've been researching new tire options for the 2G for about a year.
    I was especially interested in finding a tire that:

    (1) has LRR (Low Rolling Resistance),
    (2) gives high mileage (65K+ mileage rating),
    (3) has good all-season performance (for those thunderstorm
    downpours we have here in central Texas, but no snow here),
    (4) had good handling - including stability to eliminate
    the "dartiness" of the car.
    (5) has at least a 44psi max pressure.


    I believe I have found a tire that does all of that and also gives
    INCREASED mileage at the same time.

    The tire? Michelin Harmony. Here are the details:

    1. The Harmony (and a few others) were rated as Excellent for
    rolling resistance in the November issue of Consumer Reports. So I
    had some measured evidence of low rolling resistance.

    2. It has an 80,000 mile warranty. At around $100, the cost/mile is
    actually the same or lower than others. Its wear rating is 740.

    3. It is available nationally through Michelin dealers, which should
    make getting a replacement while on a trip fairly easy, unlike
    others (Nokians, for example) for which there are no dealers in this
    part of the country.

    4. It's an all-season tire, and is rated very well in the rain. We
    don't have a LOT of rain here in San Antonio, but it usually happens
    via thunderstorms. This makes hydroplaning resistance important.

    5. It has good grip under all conditions. No squealing around
    corners. Traction is rated "A." (Temperature is rated "B.")

    6. It has a slightly "harder" ride - at least at 44/42 where I have
    them now, in order to test them at the same pressures I used for the
    Integritys. (Max pressure is 44 psi.) Once I get a few more
    tankfulls in, I'll be testing them at 40/38 to see if it makes any
    significant difference in mileage and/or ride quality.

    7. It has softer "turn-in" than the Integitys (and probably the
    Hydroedges). For me, this is a plus. First, because it pretty much
    eliminates the "twitchiness" and "wandering" that I have had (and
    others have reported) with the Integritys. They track with much more
    stablility. Secondly, once in a turn, the car seems on rails, with
    quite a bit less obvious understeer. I know that some would want
    more sportiness, but, as has been mentioned, this is not a
    sportscar. In my case, I am always looking to improve mileage,
    and "sporty handling" isn't a huge priority when one is trying to
    drive "softly."

    8. I've driven them in some rain, and they have excellent traction
    so far (no squealing around corners or breakaway when starting from
    a stop causing the stability control to activate). Ran them through
    a few long puddles - no hydroplaning tendency.

    9. AND NOW THE REAL PLUS - INCREASED MILEAGE. After three tankfulls
    and 1,263 miles, I can report that my mileage has improved from an
    average of 48 to an average of 52. The computer reads 52.5 right
    now. That's right - a 4 mpg improvement. And I'm sure the tires are
    still being broken in. I can actually see the improvement while
    driving because I can stay in stealth mode quite a bit more, even on
    slightly uphill stretches where the ICE would always kick in before.
    During highway driving, the improvement on familiar stretches is
    obvious. And after blowing the tank average because of short trips
    or traffic, it's a lot easier to bring the mileage back up.

    Conclusion: I think I have a winner here. I'll continue to report as
    the tires continue to break in and I have more data.