Cargo Trailer Frame and Axle Construction

Everything starts with the frame

Just like the foundation of a house, if it starts off wrong, everything afterward will be a problem and sometimes it will be so bad that the trailer cannot even be completed.

Frames are normally built on a jig which is a template for construction. A jig is a custom-made table used to control the location and placement of the steel. A jig’s primary purpose is to provide repeatability, accuracy, and interchangeability in the manufacturing process.

The outside of the frame is built along with its crossmembers and the trailer tongue.

Once the parts have been welded together the axles are then installed. If axles are not properly placed, it will results in the trailer not pulling straight and excessive tire wear.

If you have uneven or excessive tire wear, check axle alignment

Important: When measuring to see if axles have been installed in the correct location, measure from the center of the tongue where the ball sits, back to the axle. Some people mistakenly think that the measurement should be from the front corner of the trailer box back to the axle.

This is incorrect. The trailer is pulled from the ball hitch, not the corner of the trailer.

Any other steel is added for items that will be installed later in the production process like E-track and D-rings.

The frame is then removed from the jig and is moved to the next construction area for wall installation.