How to Measure a Boat Trailer Axle?

How to Measure a Boat Trailer Axle

It is important to get several proper measurements of your boat trailer axle if you need to get it replaced. This article will tell you in detail how to take those measurements. So, get your tape measurer out and follow along.

4 Types of Measurements

  1. Hub face measurement
  2. Brake flange measurement
  3. Spring center measurement
  4. Overall measurement

The Hub Face Measurement

This is also referred to as the track width or the center of tire measurement. The hub base is right where your wheel would touch the outside face of the hub.

Removing your tires and wheels from your trailer’s axle will make this measurement simpler. To get your hub face measurement, hook your tape measurer on the outside face of the hub. From that end, run your tape measure across your axle to the outside of the other hub face.

The Brake Flange Measurement

Brake flanges are located towards the ends of an axle but not all axles have them. If your axle has them, then you measure the brake planes from outside of a brake flange across the axle to the outside of the other brake flange.

This is not applicable for a majority of 2,000 pound axles as they will not have a brake flange. But all 3,500 pound axles do. With 3,500 pound axles we add six inches to the outside of the brake flange measurement to get the hub face measurement.

Spring Center Measurement

This measurement refers to measuring from the center of one leaf spring, across the axle to the center of the other leaf spring. It is crucial to take this measurement properly to ensure the correct fit of your replacement axle on your trailer.

To take the spring center measurement, hook the tape measurer in the center of the leaf and run the tape across the axle to the other end at the exact same spot and take this measurement.

Spring Center Measurement

The hub face measurement can be found from the spring center measurement if your axle is broken. First, take the spring center measurement. Then, working on the intact side of your axle, take a measurement from the nearest leaf spring to the outside of the hub base.

For example, you get 7.5 inches for this, and you got 52 inches for the spring center measurement.  Then you’ll simply add 7.5+7.5+52 to give us the hub face of 67 inches. ‘7.5’ is added twice for both sides.

The Overall Measurement

The overall measurement is the total length measured from the tip of one spindle to the tip of the other one. If your axle is broken, then you can also use the spring center measurement to get this quantity.

On the good side, you measure from the center of your leaf spring out to the tip of your spindle. For example, your measurement is 10 inches. You’re then going to add 10 inches twice for both sides.

So, adding 20 inches to our spring center measurement of 52 inches would give us an overall length of 72 inches.

You can also get the hub face measurement from the overall measurement for both 2000 and 3500 pound axles. Just subtract 5 inches from the overall measurement to get the hub face measurement.

Finishing off

So, these were the ways you can easily measure the length of your axle when necessary. We hope these steps helped you to get the perfect replacement axle for you. We wish you a safe and smooth experience with your boat.