There are a few measurements that you need to be aware of regarding any trailer. To get the measurement, it's easiest if you remove your tires and wheels, or measure center of tire to center of tire. It can also be helpful to have a friend hold one side of the tape measure, but it’s not absolutely necessary.

Hub Face Measurement:

To obtain the hub face measurement, first hook your tape measure to the outside of the hub, (the part of the hub facing the wheel). Measure across the axle to the exact same spot on the opposite side. Be careful not to measure to the inside of the hub, only the outside. This is the primary measurement that is needed. The rest of the measurements below are alternative measurements that can be used to arrive at this measurement. 

Spring Center Measurement:

This measurement is critical. If the springs are misplaced due to bad measurement, you can end up bending the axles. This one is difficult to do alone. Have a friend hold the end of the tape measure right in the middle of one of the springs, while you extend to the center of the opposite spring. If taking the measurements on your own, then you can cheat by first hooking the tape measure on the outside of one spring and then extending it to the inside of the opposite spring.

The axle position in relation to the spring needs to be considered before building. The options are "overslung". where the spring is mounted over the axle, or "underslung" where the spring is mounted under the axle.

There is no advantage to either system in regards to trailer strength or ride, but does affect the height of the chassis/tongue above the road and depending on the load can aid or hinder trailer stability.

Purchasing the correct hub or drum is an important step in repairing your trailer axle.

There is simple and easy to follow steps to make sure you are getting the correct hub.

Step 1: Remove your hub or drum from your trailer axle.

Step 2: Measure your bolt pattern to identify what capacity your axle is, if it is unknown. Please see the following diagram to determine your bolt pattern.

Step 3: Now, you can also remove the front and rear bearings and seal. Once you remove the bearings, you will be able to read the number off the back of the bearings that correspond with a correct spindle size. If this number is not readable, you will be able to measure the inside dimensions of the bearing and seal in order to determine which one you need. Please see the attached pictures on how to do so.

Step 4: Pick the best hub or drum for your needs. If you are unsure, we would be happy to assist you in making the correct decision.