Essential Tips for Choosing the Replacement Leaf Spring for Your Trailer

Home » Essential Tips for Choosing the Replacement Leaf Spring for Your Trailer

Purchasing replacements for your trailer is not always straightforward. Often, you have no idea what a certain part is called, and you certainly have no idea the type or size you require.

Leaf springs provide much-needed buffering against shocks and tremors in your travel trailer, but they are not universal. Different vehicles require leaf springs of varying sorts and sizes. When the incorrect leaf spring is used, your car is left defenseless and misaligned. Before you can repair your leaf springs, you must first measure them to determine the type of replacement part you require.

leaf spring

This article will teach you everything you need to understand about changing the leaf springs on a trailer.

First, one must realize that trailer leaf springs must be chosen according to the trailer axle weight rating, spring type (Slipper or double-eye), length, and breadth parameters. Axles are typically marked with a sticker or plate indicating their weight rating.

It is critical to keep a few points in mind regarding replacement springs. When springs are still placed in the trailer suspension, they will not have their true static sizes. For correct measurement, it’s best to remove the spring because the leaf spring seems to stretch over time. After several years of heavy use, a leaf spring may flatten significantly and “grow” up to 1/2- to 3/4-inch. As a result, an initially 25-1/4 inches spring may now size closer to 26 inches.

trailer suspension


Moving on, another very important thing you must know is that there are five distinct leaf spring varieties, which fall into two broad categories (as mentioned before): double eye leaf springs and slipper springs.

1. When Should Trailer Leaf Springs Be Replaced

2. Trailer Leaf Springs Size And Axle Capacity

3. How To Choose The Right Replacement Trailer Leaf Springs

4. Procedures for Replacing Leaf Springs

5. Conclusion

1. When Should Trailer Leaf Springs Be Replaced?

Weather, aging, and excessive weight can all degrade your springs with time. At a minimum, check your trailer’s leaf springs every 12,000 miles or if you observe drooping, corrosion, fractures, or rough riding. While inspecting, keep the following in mind:

  • Examine each spring eye and take note of any cracks around the mounting plates.
  • Inspect the spring on all sides for rust and corrosion.
  • Examine any spaces between leaves for signs of wear and overburden.
  • Clean and dry your leaf spring and mounting plates regularly to limit the possibility of buildup.
  • Lubricate them as necessary to avoid early wear and to extend their life.

2. Trailer Leaf Springs Size And Axle Capacity

trailer leaf spring


The leaf spring’s middle bolt is referred to as the center point. The majority of leaf springs have two eyes at every end, where the bushings are located. Certain leaf springs are equipped with hooks or flat ends. Calculate the correct spring size for your replacement by following these steps:

  • Increase the height of your trailer: Jack up the trailer far enough, so the axle hangs freely, allowing you to detach and replace the leaf springs comfortably. Place the jack away from the suspension.
  • Eliminate the spring: The most precise approach to measure a leaf spring is to remove it from its load-bearing configuration. Disconnect and assess one spring at a time to allow the other to maintain the suspension’s position. To remove broken nuts, bolts, and mounts, you may require specialized tools.
  • Calculate the length: Measure the spring’s length from the center of one eye to the center of the opposing eye using a standard tape measure.
  • Determine the width: The breadth is determined by measuring from the bottom of the bottom leaf to the top of the top leaf with a tape measure.
  • Take measures A and B: A and B are the distances between the center point and each eye. For instance, the A measurement is the distance between the center and right eye, whereas the B measurement is the distance between the center points and the left eye.
  • Calculate the arch: Because the spring arch alters with time, measuring it provides insight into how it wears and what size to seek in a replacement. Invert the spring and use a standard tape measure to determine the distance from the ground or table to the first leaf.

3. How To Choose The Right Replacement Trailer Leaf Springs

trailer spring


Always install your trailer springs in sets to provide an even load distribution. Consider your axle capacity, the number of leaves on your current springs, and the kind and size of your springs when selecting a replacement.

The Capacity of The Axles: The capacity limit of most trailer axles is indicated on a label or plate, but you can also consult your owner’s handbook. Certain manufacturers’ websites may additionally include information about individual axles.

Number of Leaves: While measuring the spring, keep track of how many leaves it has. Hence the more leaves it has, the more stable it is — however, too many leaves will result in an overly rigid frame. Leaf springs are usually mono-leaf, consisting of a single leaf, or multi-leaf, consisting of multiple layers with clips between every layer. No holes should exist between multi-leaf springs.

Spring Dimensions and Type: Determine the type of leaf spring you’re working with once you’ve removed it. Trailer springs come in a variety of configurations.

Double-eye springs with both eyes open, and Slipper springs with one open eye, Radius-ended slipper springs, With flat end slipper springs, and Spring slippers with a hook end

In some circumstances, replacing the bushings may be sufficient if the springs remain intact and are not buckling, rusted, or extended.

4. Procedures for Replacing Leaf Springs:

  • Preparation
  • Elevate the trailerand gain access to the springs.
  • Take away the base plate
  • Install the replacement kit
  • Carry out the installation

Step 1: Make preparations

Because the existing leaves may be slightly rusted, removing them without harming any surrounding pieces utilized once the old leaves are replaced critical. Thus, before extracting leaf springs, prepare the stabilization system for the operation at hand three days in advance.

Rub lubricant around the bolts, nuts, and brackets to loosen the suspension system in readiness for the upcoming springs.

Step 2: Elevate the Trailer And Gain Access To The Springs

Set chocks at the front of the trailer’s front tires when it is stopped in an optimal working location to stop the trailer from moving forward. Loosen the rear-wheel lug nuts. Elevate the trailer’s rear end at least three inches with a hydraulic jack and secure it with a jack brace underneath the rear axle.

Undo the unfastened lug nuts and slip off the rear wheels while the trailer is hung at the rear. You should then have direct exposure to both rear leaf springs.

Step 3: Take Away the Base Plate

This step teaches you how to detach leaf springs. Find and disconnect the lower mounting stud, bolts, and shock absorbers. Remove the U-bolt nuts and the base plate. Raise the axle moderately and remove the leaf spring load from the center pin using a pry bar.

Loosen the bolt from the forward mount of the spring and place the spring’s front aside. Disconnect the spring’s rear screws and the outer plate. Release the shackle ring and shackle. The following next two stages will teach you how to install leaf springs properly.

Step 4: Install the Replacement Kit

Install the replacement shackle using the installation kit. Insert the inner-shackle pivot pin through the shackle’s metal sleeve. Ascertain that the leaf spring is properly positioned. Bear in mind that the distance between the middle and the end will vary on each side.

Place the rear leaf spring on the shackle, precisely aligned, and fasten it with latching nuts, but not too firmly. This time, use new screws, as the old screws may be worn.

Step 5: Carry Out The Installation

After securing the back of the new leaf spring in its proper location, it’s time to finish the installation. Raise the leaf spring’s front end to a position between the front mounts. Secure the bolt with the securing nut, but only lightly. The spring pack is not yet prepared for tightening.

Bring the back end down until it comes into contact with the spring and aligns the center. Install the replacement U-bolts that arrived with your replacement kit. The component is now complete and ready for tightening. Securing the nuts and bolts using a torque wrench is critical. Reevaluate the nuts and bolts after approximately seven days to ensure they are securely fastened.

leaf spring and hanger

Reapply the shock springs with the torque wrench in hand.

After completing one side’s leaf spring installation, repeat these instructions on the opposite side. After replacing the trailer’s leaf springs, reinstall the rear wheels and tighten the lug nuts on every side. Extract the jack stand from underneath the trailer and lower the rear to the ground. Check the lug nuts one more time to make sure they are securely fastened.


In conclusion, now that you know how to replace leaf springs, future leaf spring installation chores will almost certainly be much easier.

The importance of having a road-worthy trailer cannot be overemphasized. After learning about the varieties of leaf springs, you can choose the suitable style and measure for the proper replacement. The number of leaves and the spring’s maximum weight are also quite useful to know.