How to Determine Correct Replacement Double-Eye Leaf Springs for EZ-Loader Boat Trailer

Question:

Looking for a spring for my EZ LOADER Boat trailer. Measured from eye to eye center with boat on trailer. Is 25.75inch 3 leaf Thanks Much

asked by: Kevin A

Helpful Expert Reply:

It is tough to determine the actual length of a double-eye leaf spring when it is still installed in the boat trailer's suspension; it is tougher still if the weight of the boat is on the suspension.

In fact, when a leaf spring is old and well-worn, it can actually stretch or elongate slightly, meaning that if you pulled it completely out of the suspension and measured its eye-to-eye length the measurement you get could actually be longer than when that spring was brand new! We are usually talking about no more than one-half-inch of stretch but that can matter when you're trying to find new springs.

Please note that you ALWAYS want to replace leaf springs in pairs. If you replace only one you can end up with axle alignment problems and poor tracking from the moving trailer. This can lead to sway problems, especially with boat trailers that can tend to be rear-end-heavy.

Apart from spring length you also need to match springs to the axle weight rating. If an axle is rated for 3500-lbs then you want to be sure to select a pair of springs of that rating. If the eye-to-eye dimensions match and the weight rating matches up to the axle rating then the number of leaves does not matter.

Based on your 25-3/4-inch dimension you might need a spring such as 25-1/4-inch 3-leaf part # e57SR. This is rated for 4000-lb axles.

Our main page for double-eye leaf springs is linked for you, along with a helpful article concerning trailer suspensions.

expert reply by: Adam R