Jack up both sides or the trailer and support it safely on jack stands.
Remove both tires.
With the aid of your helper, measure from the front face of one hub to the front face of the other hub. This is the axle track width, one of the two dimensions you must know in order to get the correct replacement axle.
Measure the spring center distance. An easy way to do this is to hook the tape measure end on the outside of one spring and measure straight across to the inside of the other spring.Utility, boat, cargo and camper trailers all have one thing in common: an axle. Sometimes, due to bending or rust, these axles need replacement. This is a task which can be completed by a do it yourselfer with a few simple hand tools. The process starts with measuring the old axle and ordering a new one.