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Odd steering feel when making a U-turn, especially if suspension is raised

Discussion in 'Model S: Driving Dynamics' started by Shumdit, Jan 25, 2014.

  1. Shumdit

    Shumdit Member

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    I have to make a sort of very tight U-turn everyday when leaving the office as the slanted driveway faces towards the opposite direction. I have the suspension on very high to avoid scraping. When I make this u-turn it feels like a weird bump is happening almost like the tire is rolling off of the wheel. It does this when the suspension is in normal too, but not as noticeably. Anyone had a similar experience?
     
  2. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    When you are making a tight turn like that the toe-out-on-turns alignment angle is at it worst**. It's normal on every car but in an ICE car the engine vibration hides it more.

    ** TOOT is there to minimize tire scrubbing during turns. The inside tire will turn slightly more than the outside tire because the radius from the tire to the centre of the turn is smaller on the inside tire. However, it's only "perfect" in two places: straight ahead and at some predetermined angle, which is going to be located where a more normal right angle turn is made. At every other steering wheel position the tires will scrub. At the steering wheel lock, the scrubbing will be as bad as it can be.
     
  3. Shumdit

    Shumdit Member

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    Thanks for the info. This seems odd because its like there is a buildup of some sort of tension and the a "pop" as it's released (felt not heard). Is this tire scrub? I have never noticed it on any of my other cars including 2 mid-engine ones
     
  4. jerry33

    jerry33 S85 - VIN:P05130 - 3/2/13

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    It can be, or it can be the way the steering is set. I'd think it would be worthwhile to have the Service Centre check it out. I haven't noticed it on mine but I can't say that I do full lock turns all that frequently.
     
  5. ToddRLockwood

    ToddRLockwood Active Member

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    I imagine this is somewhat tire-dependent. I don't notice it with my 19" Dunlop SP Winter Sport 3D tires, except if one of the tires hits an icy patch or pavement stripe while doing a full-lock turn.
     
  6. bradhs

    bradhs Member

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    Oct 14, 2013
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    286
    Location:
    San Diego, CA
    Had the same thing happen with my car, took it in and they resolved the issue. But then it came back again a thousand miles later. Not too concerned and have notified SC so they'll check it out again next time I'm in.
     

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