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What's your Bridgestone Ecopia EP422 Tire Pressure?

Discussion in 'Gen 2 Prius Main Forum' started by tom1l21, Mar 15, 2012.

  1. tom1l21

    tom1l21 Member

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    Anyone that runs the EP422's, what do you use for tire pressure? I used to have a set of Nokian WR-G2's that I'd run anywhere from 40-42 to 43-45 (back-front). At 35k, Firestone wouldn't rotate them anymore as the tread was too worn down. I don't really take sharp corners, so the only thing I can think of is that I over inflated them, wearing down the center too much.

    I'd assume that getting an extra 20k+ out of your tires is worth more than the mpg's you'd save by running 5 more psi's.

    SO ANYWAYS, anyone that own's these, what pressure do you run them at and are they wearing evenly? Thanks in advance!
     
  2. F8L

    F8L Protecting Habitat & AG Lands

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    Do you have pics of the worn out center?

    Most of us that overinflate have very even wear. If anyone is observing uneven wear then I highly suggest adjusting your pressure higher or lower to correct the problem. It's not safe to run tires that overinflated.
     
  3. tom1l21

    tom1l21 Member

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    Nah I don't have pics, I had a bulge in the sidewall so I immediately took it to Firestone to have them replaced.

    Wouldn't overinflating lead to more wear down the center of the tire? I'm guessing that was the issue I had since the guy at Firestone (when the tires were at 35k said that the center was too worn but the two inner and outer treads were decent)
     
  4. F8L

    F8L Protecting Habitat & AG Lands

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    That is a classic symptom of overinflation. It's not common to hear about happening on a Prius or any other small car with modern narrow tires. Some of us run 50-60psi and don't. Have this issue. Maybe the Nokian you had was susceptible to over inflation.

    I would suggest keeping an eye on your new tires so you can catch uneven wear long before it causes you a problem. Many tire places give out small plastic tire tread depth "gauges" so you can keep track of tire wear. Good luck with your new ones. :)
     
  5. tom1l21

    tom1l21 Member

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    Hey thanks! I guess what I want to know is the maximum pressure I can go up to without having to worry about uneven tire wear. I simply cannot ride at stock pressures, there's just too much friction and the tires feel too "squishy." I think I'll try 40/42 and keep up on the tread depths.
     
  6. F8L

    F8L Protecting Habitat & AG Lands

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    It will vary by tire so start off with a pressure and pay careful attention to wear and adjust accordingly. I've never hear of center wear on the EP422 with moderate pressure so you you should be fine with anything at or under the sidewall max pressure. Hopefully other EP422 users will chime in with their experiences. :)
     
  7. cyclopathic

    cyclopathic Senior Member

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    I am guessing most LRR tires would be in the same boat. They are designed with softer carcass to reduce rolling resistance

    to OP it doesn't make sense to run more then 42 psi
     
  8. F8L

    F8L Protecting Habitat & AG Lands

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    Most of us run LRR tires at 42-50psi and don't have an issue.

    Yours are not wearing funny are they?
     
  9. cyclopathic

    cyclopathic Senior Member

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    no with 42 front 38 rear they wear evenly. But on new tire I saw grip drop at 44psi. Now your 44psi and and my 44 psi may be different, the gauge could be easily off by 3+ psi, and different tire construction may have impact, so YMMV
     
  10. F8L

    F8L Protecting Habitat & AG Lands

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    I agree. I'm just storing your info in my head in case someone wants recomendations for pressure in the Energy Saver A/S. :D
     
  11. bugly64

    bugly64 Junior Member

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    I just got my ep422's to start delivering on the promise. I was getting 46 mpg for the first three tanks, now I am almost done with the fourth tank and it's at 54 mpg. I run 42 front and 40 rear.
     
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  12. staze

    staze Junior Member

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    bugly64, aren't they great? I've had mine for almost 10k, and I'm averaging MUCH better mileage. I am going to crunch the actual numbers when I get to 10k (comparing my stock Turanza's, the Potenza's, and the Ecopia's), but I'm guessing they're at least 5MPG better than the Potenza's, and probably 3-4 better than the Turanza's were.
     
  13. hill

    hill High Fiber Member

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    50 P S I is a nice round number. ... that's all I'm saying :)
    SGH-I717R ? 2
     
  14. bugly64

    bugly64 Junior Member

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    I think they are great. I took a trip out to the coast and the whole time up and down windy coastal roads and highways they handled great. Also, I got really nice mileage.
     
  15. calabrsn

    calabrsn Junior Member

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    I have the EP422's. I run them at 35f/33r and got 60,000 miles on them before they needed to be replaced. Since you have had both EP422 and WRG2, how did they compare for winter traction?
     
  16. DaveinOlyWA

    DaveinOlyWA 3rd Time was Solariffic!!

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    you should inflate tires to whatever is listed on the sidewall of the tire (44 PSI i believe) this is best for longest life and even wear. what you were told by Firestone is typically to generate extra revenue for the dealership. you mentioned you replaced one tire. they alway encourage a 4 tire deal. other than that; it sounds like you did not verify their statement.

    it is not a good idea to not monitor your tires. its easy. take a toothpick or whatever you have and check tread depth inside, center, outside once a month. if you are getting uneven tire wear, it is a factory defect or an alignment issue. both should be addressed ASAP
     
  17. James D Smith

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    The only handling problem I have with the Ecopia tires is on stretches of highway where the surface has been grooved, the grooves running parallel to the direction of travel. When I get on these sections of road, the Prius pulls to one side, then to the other, about one cycle per second. It did not do this with the Yokohama original equipment. I have had the tires rotated and the car aligned, and neither made any difference. Has anyone else noticed a similar problem? Jim
     
  18. F8L

    F8L Protecting Habitat & AG Lands

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    I had that problem with the OE Yokohama S33D. My EP422s are 17" so it's not the same as the 15" version. They don't pull or wander though.