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Rear end sag

Discussion in 'Gen 2 Prius Accessories & Modifications' started by mathewwarner, Jun 16, 2011.

  1. mathewwarner

    mathewwarner Junior Member

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    I have a 1" hitch on my prius and use a Thule bike rack. When I put our two bikes on the back of the car it tends to sag quite a bit. Is there a stiffer spring available to keep the back up when I haul the bikes?
     
    #1 mathewwarner, Jun 16, 2011
  2. nerfer

    nerfer A young senior member

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    Okay, I assume you mean a 1.25" hitch. How heavy are your bikes?
    I don't think it should sag like that. Are your shocks still good? (Lean on the back end of the car and bounce it up and down a couple times, then let go. It should return to a stopped position after one bounce.)
     
    #2 nerfer, Jun 16, 2011
  3. cyclopathic

    cyclopathic Senior Member

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    #3 cyclopathic, Jun 16, 2011
  4. seilerts

    seilerts Battery Curmudgeon

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    The rear on 2004-2009 already has coilovers. An airbag solution is not possible. The problem is that the spring rate is too low. Unfortunately, the only commercially available stiffer springs that will fit also include a 1" drop typically. Thus, the solutions are custom springs or using rubber donuts in between the coils.
     
    #4 seilerts, Jun 16, 2011
  5. F8L

    F8L Protecting Habitat & AG Lands

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    At 134k, my struts were weak and my springs were sagging. If you have high mileage then you may be in the same boat. I would suggest new struts and a custom rear spring set. You could get oem springs for the front or a used set off a low mileage salvage for cheap. :)

    The manufacturer of plug in EV kits usually have good contacts for custom spring manufactures.
     
    #5 F8L, Jun 17, 2011
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  6. hyo silver

    hyo silver Awaaaaay

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    Unfortunately, rear end sag seems to be a problem for most people. :rolleyes:
     
    #6 hyo silver, Jun 17, 2011
  7. F8L

    F8L Protecting Habitat & AG Lands

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    Not me. I got buns of steel! lol
     
    #7 F8L, Jun 17, 2011
  8. mathewwarner

    mathewwarner Junior Member

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    I am at 142000 right now. The car does not bounce when I try to bounce it so the struts seem ok. I imagine the springs have lost some of their ability to "hold" the car after all of the miles.
    I don't want to lower it, just keep it stock.
    With coil overs aren't they springs and struts as one unit?
     
    #8 mathewwarner, Jun 17, 2011
  9. F8L

    F8L Protecting Habitat & AG Lands

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    My car passed the "bounce test" but I could feel the loss of strut integrity when pulling out of a driveway. It would sink pretty hard and fast when going off the "curb" and it wouldn't rebound well. Usually struts are worn by 60k so I'd say yours are definitely worn, just not broken. :)

    I wouldn't recommend lowering it for your situation which is why I recommended looking for low mileage or new OEM front springs and customs for the rear.

    True coil-overs like Mac recommends are different than the OEM setup. They usually have a screw-based adjustment which allows you to customize your ride height. Unfortunately most of them also start off lower so those may not work in your situation. Have you looked for custom springs yet?
     
    #9 F8L, Jun 17, 2011
  10. mathewwarner

    mathewwarner Junior Member

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    A little bit, tried the tire shop and they did not have any advice. Looked online a bit, but did not have much luck.
    I may check with my mechanic first.
     
    #10 mathewwarner, Jun 17, 2011
  11. F8L

    F8L Protecting Habitat & AG Lands

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    #11 F8L, Jun 17, 2011
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