Is There a Way to Determine Axle Capacity of 6 Lug Axle without Label

Updated 08/06/2021 | Published 08/05/2021

Question:

Im considering buying a new-to-me 18foot car trailer. The seller claims it was made in 2003 by Mayinch maybe from Ada, OK, which which doesnt seem to have a web site. He claims it has dual 4500-lb axles, which is an uncommon size. I dont know if theyre torsion or leaf-sprung. It has 6-bolt wheels with E-rated tires. The photos he sent me dont show any ID tags. Im hoping to drive the 90 minutes to go see it soon. In preparation for that visit, Id like to know how best to identify the axles and verify their weight rating. I dont want 3500-lb axles, and would be happy if I got 5200-lb axles. Is there a reliable way to distinguish between 3500, 4500, and 5200-lb axles by crawling under the trailer, but without taking apart the hub? Im hoping the trailer or axles have some sort of ID tag, but Im not holding my breath. All the front-facing surfaces have been sandblasted by 18 years of driving gravel roads. Attached is the best picture I have of it, which doesnt help much in identifying the axles or GVWR.

asked by: Ben H

Expert Reply:

If they are round axles you can easily measure the diameter of them to determine their 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
- 5,200-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

Another way you can determine this is by measuring diameter of the drum on the brakes. If it's 10 inch diameter then it's 3,500 but if it's 12 inch it's a 5,200 lb.

expert reply by: Jameson C