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New 20's rough ride question

Discussion in 'Lifted & Offroad Suspension' started by hunky, Jul 28, 2009.

  1. hunky

    hunky New Member

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    What air pressure are you guys running in your 20" tires. Shop that mounted the tires recommended 42psi but ride seems a little rough to me. Tires are 275-55-20 so I still have about the same sidewall as the stock tires.Truck is an '07 silverado classic,reg cab,8' bed
    Last edited: Jul 28, 2009
    #1
  2. 2COR517

    2COR517 New Member

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    What kind of truck, and what are your sidewall numbers? xx lbs at xx max psi.
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  3. 5speedsilverado

    5speedsilverado New Member

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    im guessing the truck came with 17's, and you went to a bigger rim, and kept the original tire diameter?
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  4. lerbud

    lerbud New Member

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    I have 275/55R20's and I run mine at 34 in front and 32 in the rear. It rides much smoother than when the pressures are higher.
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  5. adampaul1964

    adampaul1964 New Member

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    Actually you have less side wall than stock tires. 275/55/20 is 31.9 inches tall, 265/70/17(stock tire on my Z71) is 31.7 inches tall. The height is the same but the difference in wheel diameter means your sidewalls are 1.5 inches smaller, which will give a slightly stiffer ride because there is less "cushion", you can try airing them down but I would watch them very closely for uneven wear.
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  6. lerbud

    lerbud New Member

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    the silverado ss tire pressure on the door says 34. they come equipped with the same size tire.
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  7. hunky

    hunky New Member

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    How long have you had them? Notice any wear problems?
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  8. grimreapersshadow

    grimreapersshadow New Member

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    you should go what off what your doorjam sticker says which is proalby 35 psi even tho you changed rim size you dont wanna change your air pressure
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  9. 2ToNe04

    2ToNe04 New Member

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    of course its going to be a rougher ride you went to a bigger sized rim, with less side wall for cushion.
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  10. hunky

    hunky New Member

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    Dropped the air pressure 6psi,down to 36 and took it for a ride. Big diffrence,still " stiff" but not like riding on wooden wheels like before. I'll keep an eye on tire ware just in case.
    #10
  11. 2COR517

    2COR517 New Member

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