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Another Tire Thread - Mixing Tires

Discussion in 'Generation 1 Prius Discussion' started by Oc.dreamer, Jul 19, 2014.

  1. Oc.dreamer

    Oc.dreamer Junior Member

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    sorry.. I know there are many tire threads and for the last couple hours I've searching through them with no luck.

    I have Dunlop SP10's on my ride but today I am replacing my two rear tires with Michelin Defenders which are rated at 82T vs the SP10's 84S.

    Usually, I keep my tires inflated to 42 front, 40 rear. Now that the tires have changed, can anyone help me with what my PSI should be front and rear?
     
  2. bwilson4web

    bwilson4web BMW i3 and Model 3

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    OWCH!

    In a perfect world, get a pair of the largest diameter tires that will fit in the wheel well and put them on the front. But for now, you've joined the experimental group. So let me propose two experiments:

    1) max sidewall pressure in all tires - to establish a baseline and then drop the pressure 5 psi to the door jam pressure over a series of test segments: 10 miles each direction and cruise control maintained speed. This will let you evaluate the efficiency and handling.

    2) max sidewall pressure all tires - swap the front and back over the same route. Look for straight-line stability. Measure the indicated and actual distance traveled.

    My experience has been handling improves with the larger diameter, heavier tires on the front drive wheels. But mine are 6% larger diameter.

    Bob Wilson
     
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  3. Oc.dreamer

    Oc.dreamer Junior Member

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    Thanks bob! I'll try it out and report back in a few days
     
  4. Okinawa

    Okinawa Senior Member

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    Just what Toyota recommends. There is a sticker inside the drivers side door jamb.