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Automotive How to calculate weight of vehicle with weigh of each wheel?

  1. Jun 26, 2012 #1
    I'm doing a project regarding weight of vehicle. So we are taking reading of the weight of each of the wheel of the vehicle. So is there any formula to calculate the weigh of the vehicle that has 4 wheel.

    For Instance, wheel 1 = x kg and so on and so forth
  2. jcsd
  3. Jun 26, 2012 #2
    As long as each wheel remains at a set height* throughout the measurement, then simply add the four values together.

    * Changing the position of any wheel relative to any other wheel induces reactions in the vehicle's suspension/chassis, thus changing the relative weight. If you have only one scale and need to move it for each measurement, place removable platforms (equal in height to the scale) under each wheel. Swap a platform with the scale to take the measurement for that location.
  4. Jun 26, 2012 #3

    Ranger Mike

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    and disconnect any anti roll bars ( sway bars) and jounce the suspension each time you relocate the single scale
  5. Jun 26, 2012 #4
    oh. ok. But a problem i found was this as im doing heavy vehicle such as trailer and truck so there might be chances that the weight is not evenly distributed throughout all the wheel. would it affect the reading?
  6. Jun 27, 2012 #5
    Not exactly sure what you mean. My definition of "heavy truck & trailer" includes dual wheels and/or tandem axles.

    That could definitely complicate the procedure. If you have dual wheels, you will need to devise a platform that evenly distributes the weight of both tires onto the scale's platform.

    I've not tried it, but I believe tandem axles should be able to be weighed in the same manner I first described. As long as all of the wheel/axle heights remain the same for each measurement, then the load on each axle will remain the same.
  7. Jul 14, 2012 #6
    I can verify pantaz's theory. This is how we weigh our trucks with multi-axles on a regular basis. The key, as pantaz mentions is that all axles/wheels remain at a continuous height. A small rise or decline to the scale will alter the weights and the sum will be incorrect. To correct for the incline or decline as best as is possible requires you to keep he nearest axle, that is not being weighed at that time, as close to the scale as you can. That minimizes the difference in height as much as possible and provides a more accurate weight.
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