How to Determine Correct Leaf Spring Replacement for 12 Year Old Trailer with 3-Leaf Leaf Spring

Published 09/13/2018

Question:

I have a 12 year old trailer that broke a leaf spring that has 3 leaves. They are double eye let springs. How do I know what weight capacity my current springs are? are there common markings on them? I was thinking about going to a 4 leaf spring but I still do not know what I have to know wether I am upgrading.

asked by: STEVE M

Expert Reply:

The easiest way to determine the weight rating of your leaf spring is to note the weight rating of your axle. This can be found on a sticker or stamp near the tongue of your trailer or stamped towards the middle of your axles itself. Since you do have an older trailer you may just want to check the axles as the axles may have been swapped out sometime.

Even though it would seem that a 4-leaf spring would have a higher weight capacity than a 3-leaf spring, this actually isn't the case. To choose the correct leaf spring for your trailer you need to measure the distance between the center of the double eyelets, the width of the leaf spring, as well as note the weight rating of your axle.

Once you have this info simply choose a leaf spring that matches these specs. Please note that what you do to the suspension on one side of the trailer must be done to the other side, and also that leaf springs can stretch some over time so you may only be able to find one that is slightly shorter than your current spring.

For example, the 4-Leaf Double-Eye Spring # e54SR is rated for a 3,500 lb axle, measures 25-1/8" from center-eye to center-eye, and is 1-3/4" wide.

expert reply by: Jon G