How To Tell What Axle Weight Capacity Is

Question:

This is the only tag on the brakes are 12inch 2 axles on it trying to find out the capacity of each axles 6 lugs wheel

asked by: John D

Expert Reply:

The axle could have a tag or plate on it that will list the weight capacity. Based on the brake size you mentioned and the hub bolt pattern, my guess would be it is between 5,200 to 6,000-lbs weight capacity, but you may have to do some measuring to tell for sure.

You can also tell the weight capacity of the axle by measuring the diameter of the axle using a digital caliper like part # PTW80157.

Here is a list that will show the axle weight capacity based on the axle diameter:

Typical Axle Diameters Based on Axle Capacity
- 1,000-lb - 2,000-lb Axles: 1-1/2 inch - 1-3/4 inch diameter
- 3,500-lb Axles: 2-3/8 inch diameter
- 6,000-lb - 7,200-lb Axles: 3 inch diameter
- 8,000-lb Axles: 3-1/2 inch diameter
- 9,000-lb Axles: 4 inch diameter
- 10,000-lb Or more axles: 5 inch diameter

Those suggestions would be the easiest way to find the weight capacity on your trailer axle. If you cannot determine the weight capacity using the above suggestions the next step would be to measure the bolt pattern on the hub, size of brakes, and bearing part numbers by removing the hub and pulling the bearings. The bearing numbers should be stamped on the side of the bearing. If you cannot find the numbers you can measure the spindle where the bearings ride and also the inside measurement of the hub.

Once you have this information we can determine what capacity axles you have on your trailer.