Identifying Weight Capacity of Trailer Hubs and Axles

Question:

I inherited a trailer with what looks to be a front axle from and old vehicle with strange looking hubs. I ha e pictures available and im looking for help in identifying both peices to replace or repair. Any tips or ideas on where to look for id numbers or sns?

asked by: August H

Expert Reply:

Trailer axles will often have a sticker or plate affixed to the beam that indicates things like its manufacturer, weight capacity, serial number, etc. If you cannot find anything like that you can get a general idea of the weight rating based on the axle tube diameter and by finding the bearing parts numbers from the bearings in one of the hubs.

Two articles are linked for you; one on trailer suspensions and one on the most popular bearings used. For example, an axle with a diameter of 2-3/8-inches is often rated for 3500-lbs. A 3-inch diameter axle will usually be rated for 6K or 7K.

A trailer hub's specific bearings can also give a rough idea of axle rating. For instance, if your hub uses inner bearing # L68149 and outer bearing # L44649 it may well be a 3500-lb-rated axle. In order to replace the hubs you must use new ones that take the same set of bearings; this ensures the new hubs will fit on the axle's existing spindles.

In other cases, if you can find the trailer's main identification sticker with its GVWR (gross vehicle weight rating), which is the most it can weigh when loaded you can get an idea of axle capacity. For example, if the GVWR says 7000-lbs and the trailer has two axles, chances are good they are 3500-lb-rated axles like # e43SR.

I linked our main pages for trailer axles and for hubs. You can certainly send along photos if you need help identifying the correct items.