How to calculate axle weights

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In this short article, we explain the formulae for calculating axle weights, and take you through a simple example.

Axle Weight Distribution Formulae

To calculate distribution of weight on the front and rear axles of a truck, use these simple formulae:WB Wheelbase W Total Weight Wf Weight on front axle Wr Weight on rear axle CGF Distance from Center of Gravity to front axle

Let’s take an example

  • Step 1: Determine the Wheelbase
    • You will find this on the vehicle specification sheet. In this example, let’s say the wheelbase of the vehicle is 208 in.
  • Step 2: Determine the weight and center of gravity of the body
    • Let’s say the total weight of the body is 5000 lb, and its center of gravity is 28.2 in from the rear axle.
    • Therefore, we can calculate the Center of Gravity from the front axle to be 208 in – 28.2 in = 179.8 in.
  • Step 3: Use the formula to calculate weight on the rear axle

  • The Weight on the Rear Axle is 5000 x 179.8/208 = 4322 lb.
  • Step 4: Subtract weight on rear from total weight to find weight on front

  • This leaves the remaining weight of 5000 lb – 4322 lb = 678 lb on the front axle.

Principles of Weight Distribution

In this example, we have calculated the distribution of weight of a service body over 2 axles of a 4×2 rigid truck. The principles of calculating weight distribution are the same for this configuration as for calculating distribution of payload on a truck tractor with one or more trailers.

Looking for an easier way?

We have kept it simple here for purposes of demonstration.  If you have a more complicated configuration, or would like to be able to use a graphical interface to calculate axle weight distribution of multiple components at once, please take 2 minutes to watch this video about our Axle Weight Calculator app, or grab a free trial here.

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