How to Convert a Single Axle Trailer to a Dual Axle Trailer

Expert Reply:

Yes, as long as you lay out the axles properly a single axle trailer can be converted to a dual axle trailer.

You will need to remove the original axle, springs and spring hangers from the trailer. Once these parts are removed you will need a dual axle spring hanger kit to match the axles you are going to use and the weight rating of the axles. You will also need a second axle, U-Bolts, U-Bolt plates, springs, hubs or trailer brakes and hub/drums. If you decide to use electric brakes on the trailer you will need to get electric brake assemblies and possible brake mounting flanges for the axle or axles you will have brakes on. You will also need a set of 4 wheels and tires.

Once you have all of the parts, you will need to determine the correct position for the two axles. This is done by weighing the trailer weight under the wheels and weighing the tongue weight. Once these weights are determined add the two numbers together to get the total weight. Once the total weight is determined you need to measure the distance to the center point between the two axles. Now figure the percentage of tongue weight and if it is more than 10 percent you will need to Subtract 10 percent of the total weight from the tongue weight and divide by the total weight. Next multiply the answer by the distance between the dual axle set. The result will give you the distance that the center line of the axles should be moved forward.

If you have less than 10 percent tongue weight you will need to move the axles rearward using the following equation. Distance to move rearward will be 10 percent of total weight minus tongue weight divided by total weight then multiplied by the center line distance between the dual axle set.

We have all of the parts available online that you should need except the axles (see link).

expert reply by: Bob G