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Height adjustable Shock absorber possible?

  1. Jul 8, 2015 #1

    in my total distraction of designing the ultimate Off-road/Overland vehicle, I've been thinking about the following matter:

    Is it possible that a vehicle can be raised/lowered by pumping/removing extra oil into the shock absorber?

    And if so, would it affect the ride? Could it be done automated by a pump?

    Should I have already patented this idea :-p? This is really stuck in my mind and sadly I don't have the resources or expertise to fabricate something like this!
  2. jcsd
  3. Jul 8, 2015 #2

    jack action

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  4. Jul 8, 2015 #3
    Fast answer, great!

    I was already thinking something like that, that the ride height isn't detirmened by the shock absorber. But in the following video they explain how to adjust air shocks. In which they say that fluid is added to raise the ride height. The car also doesn't have any springs, it only has bumpstops and the shocks to control the vertical movement of the axle.

    Here is the link:

    Is this somehow a completely different suspension to the traditional kind?


    Hmmm, I seem to have misunderstood what he was saying. It seems the amount of gas sets the ride height.

    So let me rephrase my question:

    Could the amount of gas in an airshock be altered by using a compressor and a reservoir?
    Last edited: Jul 8, 2015
  5. Jul 8, 2015 #4

    jack action

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    Air shock is a misleading name. Actually, it's a shock with an integrated air spring, which plays a role similar to the coil-over spring. The advantage of the air spring over the coil spring (whether integrated within a shock or not) is that its stiffness can be adjusted with air pressure. The air spring can be a stand-alone or use in conjunction with another more common coil or leaf spring.

    Here are videos from a company called Ridetech that specializes in air spring suspensions. The first video shows their separate coil and spring suspension and the next one their shock with integrated spring (or vice-versa?):

    The next product is from a company called Airlift and it is an air shock ... without the shock! i.e. it's an air spring which is just an air bag that you put within the spring to achieve the same goal: creating an adjustable ride height vehicle.


    The problem with the air spring is that it stiffens the ride when you increase the pressure ... unless you add weight on the vehicle. Which is why they are usually use to level a vehicle that is often loaded and unloaded. The spring I showed you in the previous post increases or decreases the ride height without altering the spring stiffness and therefore you keep the same ride quality if the weight is unchanged.
  6. Jul 8, 2015 #5


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    You can fit your car with a custom air suspension kit which is capable of changing its ride height. This is how so-called "low riders" work:


    Most of these vehicles are customized for street use only. IDK of any systems which are used for off-road vehicles.
  7. Mar 22, 2016 #6
    Citroen has had hydraulic ride height adjustable suspension for DECADES... A pump is driven off the engine to supply the fluid pressure. To change a tire, you would raise the car up to max, then place the jack stand under the corresponding wheel change pad, under the body/ frame, and then lower the car suspension.. Voila, tire off the ground.. If you could find a re-buildable system from a wreck, you'd be alot further along, and you'd just have to engineer it from that point..
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