How to Estimate Trailer Axle Weight Capacity from Axle Diameter

Updated 06/23/2016 | Published 06/21/2016

Products Featured in This Question

Dexstar Vintage Steel Wheel w/ +5 mm Offset - 13" x 4-1/2" Rim - 4 on 9.44 - Silver

(248)

$181.37

Dexter Trailer Axle w/ Idler Hubs - EZ-Lube - 5 on 4-1/2 Bolt Pattern - 89" Long - 3,500 lbs

(406)

$416.30

Question:

I have a 1974 Little Gem Travel Trailer, Serial number 16798. I need know what the axle weight capacity is and am having a very hard time finding any info for it since its so old and that monufactureer has since gone out of business. It was refurbished and is being converted into a tiny house. I just need to know the max weight the axles can hold. Supposedly it should be on the trailer somewhere. Where would I find it on the trailer? And what if it is was removed when it was refurbished? How would I find out the max weight? Any info would be greatly appreciated.

asked by: Renee

Helpful Expert Reply:

Thank you for the photo of your converted trailer. Nice!

Trailer axles usually leave the factory with a sticker or place installed directly on the axle beam that indicates the manufacturer, part number and weight rating. You can check the axles on your trailer for this sticker or plate. Given the age of the trailer these may be long gone.

If none is present on the axles then you can note the axle diameter as this can get you in the ballpark in terms of weight rating.

An axle diameter of 1-1/2- to 1-3/4-inches usually corresponds to an axle weight rating of 1000- to 2000-lbs. 2-3/8- up to 3-1/2-inch axles are often rated for 3500-lbs. 3-inch axles often carry a 6000- to 7000-lb rating. Please refer to the linked article on trailer suspensions for more on axle ratings.

I note that you have vintage style wheels on the trailer. We do still offer one wheel of this type, part # AM20208 from Dexter. Since you have such a nice trailer house on that frame, you may want to consider changing your two axles to moderns ones with new hubs in a commonly-available bolt pattern.

We do offer complete axle kits in various lengths and weight ratings. You can click on the link provided to see axle kits like # 35545I-EZ-89. This 89-inch 3500-lb axle comes with 5-on-4-1/2 bolt pattern idler hubs and has 74-inch spring centers.