1.Hub Face Measurement

The hub face measurement, also known as the axle track, is crucial when replacing an axle. This measurement involves gauging the distance from the outer edge of one hub face to the outer edge of the opposite hub face, where the axle contacts the wheel and tire.

2.Spring Center Measurement

The spring center measurement is crucial to ensure proper alignment of the axle's springs. This measurement ensures that the new axle's springs are positioned similarly to the old ones, preventing any interference with the trailer's wheels, tires, or other components.

To measure the spring center, position your tape measure at the center of one spring and extend it to the center of the opposite spring. This method remains consistent whether your trailer's springs are mounted above or below the axle. If you're measuring solo, you can hook the tape measure on the outside edge of one spring and measure to the inside edge of the other spring. This measurement is equivalent to a center-to-center measurement and ensures accuracy even without assistance.

When it comes to axle beam diameter, there are a few things to keep in mind.

  • For axles that can carry up to 3,500 pounds, the regular round tube axle has a diameter of 2 3/8 inches.
  • But if you're dealing with heavier axles, from 5,200 to 7,000 pounds, they typically have a thicker diameter of 3 inches.
  • You can check this by measuring from the top to the bottom of the axle using calipers for accurate results.

Bolt Pattern

  • For axles rated at 3,500 pounds, they usually have a 5-lug bolt pattern, with the most common one being 5 lugs on a 4.5-inch pattern. But remember, there are four variations of this pattern.
  • For axles rated at 5,200 pounds, a typical bolt pattern is 6 lugs on a 5.5-inch pattern.
  • And for heavy-duty axles rated at 7,000 pounds, they often have an 8-lug bolt pattern on a 6.5-inch pattern

Step-by-Step Guide:

  1. Get Ready: Park your trailer on a flat surface and make sure it's securely in place.
  2. Measure Hub Face: Use a tape measure to find the distance from one hub face to the opposite one.
  3. Measure Spring Center: Find the distance between the centers of the spring pads.
  4. Note Axle Beam Diameter: If needed, use a caliper for an accurate measurement of the axle beam diameter.
  5. Identify Bolt Pattern: Measure the distance between bolts opposite each other for 6 and 8 lug patterns, or follow specific methods for a 5 lug pattern.

3. Here are some additional methods to measure a trailer axle:

1. To check if you're missing an axle hub or if the axle is bent:

Measuring a trailer axle, especially when parts are missing or it's bent, might feel tricky, but there are methods to figure out the dimensions you need for fixing or replacing it. One way is the Spring Center+Overhang method. Here's how it works:

  • Spring Center: Measure the distance between the centers of the spring pads on each side of the trailer.
  • Overhang: Measure the distance from the center of the spring pad to the center of the missing hub or the bent part of the axle.
  • Calculation: To calculate the hub face measurement, add the spring center measurement to twice the overhang. The hub face is the total width of the axle, measured from one hub’s flat face (where the wheel mounts) to the other. (Spring Center + 2 × Overhang = Hub Face)

2. End-to-End Spindle Measurement

To obtain the end-to-end spindle measurement, start by removing both wheels. Then, hook your tape measure on one spindle's end and extend it to the end of the opposite spindle. Ensure that the new axle you're considering purchasing matches this end-to-end measurement.

While not as precise as measuring for hub face or spring center, this method can still assist in narrowing down axle options or serve as a double-check to ensure you're selecting the correct axle for your needs.

3. To measure the overall length for a determined hub face, follow these steps:

  1. For 2,000 lb and 3,500 lb axles: Subtract 5 inches from the overall length.
  2. For 6,000 lb and 7,000 lb axles: Subtract 6 inches from the overall length.

Always remember these important points:

    1. Double-Check: Verify your measurements to ensure accuracy. Mistakes can lead to improper fitting or unsafe conditions.
    2. Seek Professional Advice: If you're unsure about any specifications or measurements, don't hesitate to consult with professionals or contact the manufacturer. They can provide valuable guidance to ensure you get it right.
    3. Safety First: Taking the time to get accurate measurements is vital for your trailer's performance and safety. Rushing through the process can lead to problems down the road.